Method and System for Making a Fuel Cell

ABSTRACT

Herein disclosed is a method of making a fuel cell including forming an anode, a cathode, and an electrolyte using an additive manufacturing machine. The electrolyte is between the anode and the cathode. Preferably, electrical current flow is perpendicular to the electrolyte in the lateral direction when the fuel cell is in use. Preferably, the method comprises making an interconnect, a barrier layer, and a catalyst layer using the additive manufacturing machine.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit under 35 U.S.C. 119(e) of U.S.Provisional Patent Application No. 62/756,257 filed Nov. 6, 2018, U.S.Provisional Patent Application No. 62/756,264 filed Nov. 6, 2018, U.S.Provisional Patent Application No. 62/757,751 filed Nov. 8, 2018, U.S.Provisional Patent Application No. 62/758,778 filed Nov. 12, 2018, U.S.Provisional Patent Application No. 62/767,413 filed Nov. 14, 2018, U.S.Provisional Patent Application No. 62/768,864 filed Nov. 17, 2018, U.S.Provisional Patent Application No. 62/771,045 filed Nov. 24, 2018, U.S.Provisional Patent Application No. 62/773,071 filed Nov. 29, 2018, U.S.Provisional Patent Application No. 62/773,912 filed Nov. 30, 2018, U.S.Provisional Patent Application No. 62/777,273 filed Dec. 10, 2018, U.S.Provisional Patent Application No. 62/777,338 filed Dec. 10, 2018, U.S.Provisional Patent Application No. 62/779,005 filed Dec. 13, 2018, U.S.Provisional Patent Application No. 62/780,211 filed Dec. 15, 2018, U.S.Provisional Patent Application No. 62/783,192 filed Dec. 20, 2018, U.S.Provisional Patent Application No. 62/784,472 filed Dec. 23, 2018, U.S.Provisional Patent Application No. 62/786,341 filed Dec. 29, 2018, U.S.Provisional Patent Application No. 62/791,629 filed Jan. 11, 2019, U.S.Provisional Patent Application No. 62/797,572 filed Jan. 28, 2019, U.S.Provisional Patent Application No. 62/798,344 filed Jan. 29, 2019, U.S.Provisional Patent Application No. 62/804,115 filed Feb. 11, 2019, U.S.Provisional Patent Application No. 62/805,250 filed Feb. 13, 2019, U.S.Provisional Patent Application No. 62/808,644 filed Feb. 21, 2019, U.S.Provisional Patent Application No. 62/809,602 filed Feb. 23, 2019, U.S.Provisional Patent Application No. 62/814,695 filed Mar. 6, 2019, U.S.Provisional Patent Application No. 62/819,374 filed Mar. 15, 2019, U.S.Provisional Patent Application No. 62/819,289 filed Mar. 15, 2019, U.S.Provisional Patent Application No. 62/824,229 filed Mar. 26, 2019, U.S.Provisional Patent Application No. 62/825,576 filed Mar. 28, 2019, U.S.Provisional Patent Application No. 62/827,800 filed Apr. 1, 2019, U.S.Provisional Patent Application No. 62/834,531 filed Apr. 16, 2019, U.S.Provisional Patent Application No. 62/837,089 filed Apr. 22, 2019, U.S.Provisional Patent Application No. 62/840,381 filed Apr. 29, 2019, U.S.Provisional Patent Application No. 62/844,125 filed May 7, 2019, U.S.Provisional Patent Application No. 62/844,127 filed May 7, 2019, U.S.Provisional Patent Application No. 62/847,472 filed May 14, 2019, U.S.Provisional Patent Application No. 62/849,269 filed May 17, 2019, U.S.Provisional Patent Application No. 62/852,045 filed May 23, 2019, U.S.Provisional Patent Application No. 62/856,736 filed Jun. 3, 2019, U.S.Provisional Patent Application No. 62/863,390 filed Jun. 19, 2019, U.S.Provisional Patent Application No. 62/864,492 filed Jun. 20, 2019, U.S.Provisional Patent Application No. 62/866,758 filed Jun. 26, 2019, U.S.Provisional Patent Application No. 62/869,322 filed Jul. 1, 2019, U.S.Provisional Patent Application No. 62/875,437 filed Jul. 17, 2019, U.S.Provisional Patent Application No. 62/877,699 filed Jul. 23, 2019, U.S.Provisional Patent Application No. 62/888,319 filed Aug. 16, 2019, U.S.Provisional Patent Application No. 62/895,416 filed Sep. 3, 2019, U.S.Provisional Patent Application No. 62/896,466 filed Sep. 5, 2019, U.S.Provisional Patent Application No. 62/899,087 filed on Sep. 11, 2019,U.S. Provisional Patent Application No. 62/904,683 filed on Sep. 24,2019, U.S. Provisional Patent Application No. 62/912,626 filed on Oct.8, 2019, U.S. Provisional Patent Application No. 62/925,210 filed onOct. 23, 2019, U.S. Provisional Patent Application No. 62/927,627 filedon Oct. 29, 2019, U.S. Provisional Patent Application No. 62/928,326filed on Oct. 30, 2019. The disclosures of each of said applications arehereby incorporated herein by reference.

TECHNICAL FIELD

This invention relates to manufacturing methods and systems. Moreparticularly, this invention relates to methods and systems ofmanufacturing a fuel cell.

BACKGROUND

A fuel cell is an electrochemical apparatus that converts the chemicalenergy from a fuel into electricity through an electrochemical reaction.Sometimes, the heat generated by a fuel cell is also usable. There aremany types of fuel cells. For example, proton-exchange membrane fuelcells (PEMFCs) are built out of membrane electrode assemblies (MEA)which include the electrodes, electrolyte, catalyst, and gas diffusionlayers. An ink of catalyst, carbon, and electrode are sprayed or paintedonto the solid electrolyte and carbon paper is hot pressed on eitherside to protect the inside of the cell and also act as electrodes. Themost important part of the cell is the triple phase boundary where theelectrolyte, catalyst, and reactants mix and thus where the cellreactions actually occur. The membrane must not be electricallyconductive so that the half reactions do not mix.

PEMFC is a good candidate for vehicle and other mobile applications ofall sizes (e.g., mobile phones) because it is compact. However, thewater management is crucial to performance: too much water will floodthe membrane, too little will dry it; in both cases, power output willdrop. Water management is a difficult problem in PEM fuel cell systems,mainly because water in the membrane is attracted toward the cathode ofthe cell through polarization. Furthermore, the platinum catalyst on themembrane is easily poisoned by carbon monoxide (CO level needs to be nomore than one part per million). The membrane is also sensitive tothings like metal ions, which can be introduced by corrosion of metallicbipolar plates, or metallic components in the fuel cell system, or fromcontaminants in the fuel and/or oxidant.

Solid oxide fuel cells (SOFCs) are a different class of fuel cells thatuse a solid oxide material as the electrolyte. SOFCs use a solid oxideelectrolyte to conduct negative oxygen ions from the cathode to theanode. The electrochemical oxidation of the oxygen ions with fuel (e.g.,hydrogen, carbon monoxide) occurs on the anode side. Some SOFCs useproton-conducting electrolytes (PC-SOFCs), which transport protonsinstead of oxygen ions through the electrolyte. Typically, SOFCs usingoxygen ion conducting electrolytes have higher operating temperaturesthan PC-SOFCs. In addition, SOFCs do not typically require expensiveplatinum catalyst material, which is typically necessary for lowertemperature fuel cells such as proton-exchange membrane fuel cells(PEMFCs), and are not vulnerable to carbon monoxide catalyst poisoning.Solid oxide fuel cells have a wide variety of applications, such asauxiliary power units for homes and vehicles as well as stationary powergeneration units for data centers. SOFCs comprise interconnects, whichare placed between each individual cell so that the cells are connectedin series and that the electricity generated by each cell is combined.One category of SOFC is segmented-in-series (SIS) type SOFC, in whichelectrical current flow is parallel to the electrolyte in the lateraldirection. Contrary to the SIS type SOFC, a different category of SOFChas electrical current flow perpendicular to the electrolyte in thelateral direction. These two categories of SOFCs are connecteddifferently and made differently.

For the fuel cell to function properly and continuously, components forbalance of plant (BOP) are needed. For example, the mechanical balanceof plant includes air preheater, reformer and/or pre-reformer,afterburner, water heat exchanger, anode tail gas oxidizer. Othercomponents are also needed, such as, electrical balance of plantincluding power electronics, hydrogen sulfide sensors, and fans. TheseBOP components are often complex and expensive. Fuel cells and fuel cellsystems are simply examples of the necessity and interest to developadvanced manufacturing system and method such that these efficientsystems may be economically produced and widely deployed.

SUMMARY

Herein disclosed is a method of making a fuel cell comprising: formingan anode using an additive manufacturing machine; forming a cathodeusing the additive manufacturing machine; and forming an electrolyteusing the additive manufacturing machine, wherein the electrolyte isbetween the anode and the cathode. In an embodiment, electrical currentflow is perpendicular to the electrolyte in the lateral direction whenthe fuel cell is in use. In an embodiment, a method of making a fuelcell comprises (a) producing an anode using an additive manufacturingmachine (AMM); (b) creating an electrolyte using the additivemanufacturing machine; (c) making a cathode using the additivemanufacturing machine; wherein electrical current flow is perpendicularto the electrolyte in the lateral direction when the fuel cell is inuse. In an embodiment, the fuel cell is a non-SIS type SOFC. In anembodiment, the method comprises assembling the anode, the electrolyte,and the cathode using the additive manufacturing machine. In anembodiment, the method comprises making at least one barrier layer usingthe additive manufacturing machine or making a catalyst layer using theadditive manufacturing machine. In an embodiment, the method comprisesmaking an interconnect using the additive manufacturing machine. In anembodiment, a first fuel cell is stacked with a second fuel cell suchthat the interconnect is in contact with surface A of an electrode ofthe first fuel cell, wherein surface A has an area larger than theaverage surface area of the electrode of the first fuel cell; and theinterconnect is in contact with surface B of an electrode of the secondfuel cell, wherein surface B has an area larger than the average surfacearea of the electrode of the second fuel cell, wherein the averagesurface area of the electrode is the total surface area of the electrodedivided by the number of surfaces of the electrode.

In an embodiment, the method comprises heating the anode, or theelectrolyte, or the cathode, or combinations thereof. In an embodiment,heating is performed using electromagnetic radiation (EMR). In anembodiment, the EMR has a wavelength ranging from 10 to 1500 nm and theEMR has a minimum energy density of 0.1 Joule/cm². In an embodiment, theEMR is provided by a xenon lamp. In various embodiments, peak wavelengthis based on relative irradiance with respect to wavelength. In anembodiment, the EMR comprises UV light, near ultraviolet light, nearinfrared light, infrared light, visible light, laser, electron beam,microwave. In an embodiment, heating is performed in situ. In anembodiment, said additive manufacturing machine utilizes a multi-nozzleadditive manufacturing method. In an embodiment, said additivemanufacturing machine utilizes a deposition method comprising materialjetting, binder jetting, inkjet printing, aerosol jetting, or aerosoljet printing, vat photopolymerization, powder bed fusion, materialextrusion, directed energy deposition, sheet lamination, ultrasonicinkjet printing, or combinations thereof.

Also discussed herein is an additive manufacturing machine (AMM)comprising a chamber, wherein said chamber is configured to receive amaterial and configured to allow the material to be heated and reach atemperature of at least 300° C. In an embodiment, said material forms aportion of a fuel cell. In an embodiment, said chamber is configured toheat the material in situ. In an embodiment, said chamber is heated byelectromagnetic radiation (EMR), or plasma, or hot fluid, or a heatingelement, or combinations thereof. In an embodiment, the EMR is providedby a xenon lamp. In an embodiment, said chamber is configured to befilled with a fluid. In an embodiment, said fluid in the chamber ischanged or replaced. In an embodiment, said fluid comprises an inert gaswith no significant amount of oxygen. In an embodiment, said chamber issealed, or enclosed, or open, or without top and side walls. In anembodiment, the additive manufacturing machine is configured to deploymaterial jetting, binder jetting, inkjet printing, aerosol jetting, oraerosol jet printing, vat photopolymerization, powder bed fusion,material extrusion, directed energy deposition, sheet lamination,ultrasonic inkjet printing, or combinations thereof.

Further disclosed herein is a system comprising at least one depositionnozzle, an electromagnetic radiation (EMR) source, and a depositionreceiver, wherein the deposition receiver is configured to receive bothEMR exposure and deposition. In an embodiment, the deposition receiveris configured to receive both EMR exposure and deposition at the samelocation. In an embodiment, the deposition receiver is configured tomove such that the receiver receives deposition for a first time periodand to receive EMR exposure for second time period. In an embodiment,the EMR source comprises a xenon lamp. In an embodiment, the EMR sourceis a xenon lamp.

Further aspects and embodiments are provided in the following drawings,detailed description and claims. Unless specified otherwise, thefeatures as discussed herein are combinable and all such combinationsare within the scope of this disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The following drawings are provided to illustrate certain embodimentsdescribed herein. The drawings are merely illustrative and are notintended to limit the scope of claimed inventions and are not intendedto show every potential feature or embodiment of the claimed inventions.The drawings are not necessarily drawn to scale; in some instances,certain elements of the drawing may be enlarged with respect to otherelements of the drawing for purposes of illustration.

FIG. 1 illustrates a fuel cell comprising an anode, an electrolyte, anda cathode, according to an embodiment of this disclosure.

FIG. 2 illustrates a fuel cell comprising an anode, an electrolyte, atleast one barrier layer, and a cathode, according to an embodiment ofthis disclosure.

FIG. 3 illustrates a fuel cell comprising an anode, a catalyst, anelectrolyte, at least one barrier layer, and a cathode, according to anembodiment of this disclosure.

FIG. 4 illustrates a fuel cell comprising an anode, a catalyst, anelectrolyte, at least one barrier layer, a cathode, and an interconnect,according to an embodiment of this disclosure.

FIG. 5 illustrates a fuel cell stack, according to an embodiment of thisdisclosure.

FIG. 6 illustrates a method and system of integrated deposition andheating using electromagnetic radiation (EMR), according to anembodiment of this disclosure.

FIG. 7 illustrates SRTs of a first composition and a second compositionas a function of temperature, according to an embodiment of thisdisclosure.

FIG. 8 illustrates a process flow for forming and heating at least aportion of a fuel cell, according to an embodiment of this disclosure.

FIG. 9 illustrates maximum height profile roughness, according to anembodiment of this disclosure.

FIG. 10 is a scanning electron microscopy image (side view) illustratingan electrolyte (YSZ) printed and sintered on an electrode (NiO—YSZ),according to an embodiment of this disclosure.

FIG. 11A illustrates a perspective view of a fuel cell cartridge (FCC),according to an embodiment of this disclosure.

FIG. 11B illustrates cross-sectional views of a fuel cell cartridge(FCC), according to an embodiment of this disclosure.

FIG. 11C illustrates top view and bottom view of a fuel cell cartridge(FCC), according to an embodiment of this disclosure.

DETAILED DESCRIPTION

The following description recites various aspects and embodiments of theinventions disclosed herein. No particular embodiment is intended todefine the scope of the invention. Rather, the embodiments providenon-limiting examples of various compositions, and methods that areincluded within the scope of the claimed inventions. The description isto be read from the perspective of one of ordinary skill in the art.Therefore, information that is well known to the ordinarily skilledartisan is not necessarily included.

The following terms and phrases have the meanings indicated below,unless otherwise provided herein. This disclosure may employ other termsand phrases not expressly defined herein. Such other terms and phrasesshall have the meanings that they would possess within the context ofthis disclosure to those of ordinary skill in the art. In someinstances, a term or phrase may be defined in the singular or plural. Insuch instances, it is understood that any term in the singular mayinclude its plural counterpart and vice versa, unless expresslyindicated to the contrary.

As used herein, the singular forms “a,” “an,” and “the” include pluralreferents unless the context clearly dictates otherwise. For example,reference to “a substituent” encompasses a single substituent as well astwo or more substituents, and the like.

As used herein, “for example,” “for instance,” “such as,” or “including”are meant to introduce examples that further clarify more generalsubject matter. Unless otherwise expressly indicated, such examples areprovided only as an aid for understanding embodiments illustrated in thepresent disclosure and are not meant to be limiting in any fashion. Nordo these phrases indicate any kind of preference for the disclosedembodiment.

As used herein, compositions and materials are used interchangeablyunless otherwise specified. Each composition/material may have multipleelements, phases, and components. Heating as used herein refers toactively adding energy to the compositions or materials. In situ in thisdisclosure refers to the treatment (e.g., heating) process beingperformed either at the same location or in the same device of theforming process of the compositions or materials. For example, thedeposition process and the heating process are performed in the samedevice and at the same location, in other words, without changing thedevice and without changing the location within the device. For example,the deposition process and the heating process are performed in the samedevice at different locations, which is also considered in situ.

Additive manufacturing (AM) refers to a group of techniques that joinmaterials to make objects, usually slice by slice or layer upon layer.AM is contrasted to subtractive manufacturing methodologies, whichinvolve removing sections of a material by machining or cutting away. AMis also referred as additive fabrication, additive processes, additivetechniques, additive layer manufacturing, layer manufacturing, andfreeform fabrication. Some examples of AM are extrusion,photopolymerization, powder bed fusion, material jetting, binderjetting, directed energy deposition, lamination, direct metal lasersintering (DMLS), selective laser sintering (SLS), selective lasermelting (SLM), directed energy deposition (DED), laser metal deposition(LMD), electron beam (EBAM), and metal binder jetting. A 3D printer is atype of AM machine (AMM). An inkjet printer or ultrasonic inkjet printerare also AMM's.

As used herein, the phrase “strain rate tensor” or “SRT” is meant torefer to the rate of change of the strain of a material in the vicinityof a certain point and at a certain time. It can be defined as thederivative of the strain tensor with respect to time. When SRTs ordifference of SRTs are compared in this disclosure, it is the magnitudethat is being used.

As used herein, lateral refers to the direction that is perpendicular tothe stacking direction of the layers in a non-SIS type fuel cell. Thus,lateral direction refers to the direction that is perpendicular to thestacking direction of the layers in a fuel cell or the stackingdirection of the slices to form an object during deposition. Lateralalso refers to the direction that is the spread of deposition process.

Syngas (i.e., synthesis gas) in this disclosure refers to a mixtureconsisting primarily of hydrogen, carbon monoxide, and carbon dioxide.

In this disclosure, absorbance is a measure of the capacity of asubstance to absorb electromagnetic radiation (EMR) of a wavelength.

Absorption of radiation refers to the energy absorbed by a substancewhen exposed to the radiation.

The typical manufacturing process of a fuel cell can sometimes requiremore than 100 steps utilizing dozens of machines. According to anembodiment of this disclosure, a method of making a fuel cell comprisesusing only one additive manufacturing machine (AMM) to manufacture afuel cell, wherein the fuel cell comprises an anode, electrolyte, and acathode. In an embodiment, the fuel cell comprises at least one barrierlayer, for example, between the electrolyte and the cathode, or betweenthe electrolyte and the cathode, or both. The at least one barrier layeris also preferably made by the same single additive manufacturingmachine. In an embodiment, the additive manufacturing machine alsoproduces an interconnect and assembles the interconnect with the anode,the cathode, the barrier layer(s), and the electrolyte.

In an embodiment, the interconnect, the anode, the electrolyte, and thecathode are formed layer on layer, for example, printed layer on layer.It is important to note that, within the scope of the invention, theorder of forming these layers can be varied. In other words, either theanode or the cathode can be formed before the other. Naturally, theelectrolyte is formed so that it is between the anode and the cathode.The barrier layer(s), catalyst layer(s) and interconnect(s) are formedso as to lie in the appropriate position within the fuel cell to performtheir functions.

In an embodiment, each of the interconnect, the anode, the electrolyte,and the cathode has six faces. In some cases, the anode is printed onthe interconnect and is in contact with the interconnect; theelectrolyte is printed on the anode and is in contact with the anode;the cathode is printed on the electrolyte and is in contact with theelectrolyte. Each print is sintered, for example, using EMR. As such,the assembling process and the forming process are simultaneous, whichis not possible with conventional methods. Moreover, with the preferredembodiment, the needed electrical contact and gas tightness are alsoachieved at the same time. In contrast, conventional fuel cellassembling processes are required to accomplish this via pressing orcompression of the fuel cell components or layers. The pressing orcompression process can cause cracks in the fuel cell layers that areundesirable.

In various embodiments, the single AMM makes a first fuel cell, whereinthe fuel cell comprises the anode, the electrolyte, the cathode, the atleast one barrier layer, and the interconnect. In various embodiments,the single AMM makes a second fuel cell. In various embodiments, thesingle AMM assembles the first fuel cell with the second fuel cell toform a fuel cell stack. In various embodiments, the production using AMMis repeated as many times as desired; and a fuel cell stack is assembledusing the AMM. In an embodiment, the various layers of the fuel cell areproduced by the AMM above ambient temperature, for example, above 100°C., from 100° C. to 500° C., from 100° C. to 300° C. In variousembodiments, the fuel cell or fuel cell stack is heated after it isformed/assembled. In an embodiment, the fuel cell or fuel cell stack isheated at a temperature above 500° C. In an embodiment, the fuel cell orfuel cell stack is heated at a temperature from 500° C. to 1500° C.

In various embodiments, the AMM comprises a chamber where themanufacturing of fuel cells takes place. This chamber is able towithstand high temperature to enable the production of the fuel cells.In an embodiment, this high temperature is at least 300° C. In anembodiment, this high temperature is at least 500° C. In an embodiment,this high temperature is at least 1000° C. In an embodiment, this hightemperature is at least 1500° C. In some cases, this chamber alsoenables heating of the fuel cells to take place in the chamber. Variousheating methods are applied, such as laser heating/curing,electromagnetic wave heating, hot fluid heating, or heating elementassociated with the chamber. The heating element may be a heatingsurface or a heating coil or a heating rod and is associated with thechamber such that the content in the chamber is heated to the desiredtemperature range. In various embodiments, the chamber of the AMM isable to apply pressure to the fuel cell(s) inside, for example, via amoving element (e.g., a moving stamp or plunger). In variousembodiments, the chamber of the AMM is able to withstand pressure. Thechamber can be pressurized by a fluid and de-pressurized as desired. Thefluid in the chamber can also be changed/replaced as needed.

In an embodiment, the fuel cell or fuel cell stack is heated using EMR.In an embodiment, the fuel cell or fuel cell stack is heated using ovencuring. In an embodiment, the laser beam is expanded (for example, bythe use of one or more mirrors) to create a heating zone with uniformpower density. In an embodiment, each layer of the fuel cell is EMRcured separately. In an embodiment, a combination of fuel cell layers isEMR cured separately, for example, a combination of the anode, theelectrolyte, and the cathode layers. In an embodiment, a first fuel cellis EMR cured, assembled with a second fuel cell, and then the secondfuel cell is EMR cured. In an embodiment, a first fuel cell is assembledwith a second fuel cell, and then the first fuel cell and the secondfuel cell are EMR cured separately. In an embodiment, a first fuel cellis assembled with a second fuel cell to form a fuel cell stack, and thenthe fuel cell stack is EMR cured. The sequence of laser heating/curingand assembling is applicable to all other heating methods.

In an embodiment, the AMM produces each layer of a multiplicity of fuelcells simultaneously. In an embodiment, the AMM assembles each layer ofa multiplicity of fuel cells simultaneously. In an embodiment, heatingof each layer or heating of a combination of layers of a multiplicity offuel cells takes place simultaneously. All the discussion and all thefeatures herein for a fuel cell or a fuel cell stack are applicable tothe production, assembling, and heating of the multiplicity of fuelcells. In an embodiment, a multiplicity of fuel cells is 20 or more. Inan embodiment, a multiplicity of fuel cells is 50 or more. In anembodiment, a multiplicity of fuel cells is 80 or more. In anembodiment, a multiplicity of fuel cells is 100 or more. In anembodiment, a multiplicity of fuel cells is 500 or more. In anembodiment, a multiplicity of fuel cells is 800 or more. In anembodiment, a multiplicity of fuel cells is 1000 or more. In anembodiment, a multiplicity of fuel cells is 5000 or more. In anembodiment, a multiplicity of fuel cells is 10,000 or more.

Herein also disclosed is a treatment process that has one or more of thefollowing effects: heating, drying, curing, sintering, annealing,sealing, alloying, evaporating, restructuring, foaming. The treatmentprocess comprises exposing a substrate to a source of electromagneticradiation (EMR). In an embodiment, the EMR treats a substrate having afirst material. In various embodiments, the EMR has a wavelength rangingfrom 10 to 1500 nm. In various embodiments, the EMR has a minimum energydensity of 0.1 Joule/cm². In an embodiment, the EMR has a burstfrequency of 1-1000 Hz or 10-1000 Hz. In an embodiment, the EMR has anexposure distance of no greater than 50 mm. In an embodiment, the EMRhas an exposure duration no less than 0.1 ms or 1 ms. In an embodiment,the EMR is applied with a capacitor voltage of no less than 100V. Forexample, a single pulse of EMR is applied with an exposure distance ofabout 10 mm and an exposure duration of 5-20 ms.

The following detailed discussion takes the production of solid oxidefuel cells (SOFCs) as an example. As one in the art recognizes, themethodology and the manufacturing process are applicable to anyelectrochemical device, reactor, vessel, catalyst, etc.

Additive Manufacturing

In a first aspect, the invention is a method of making a fuel cellcomprising (a) producing an anode using an additive manufacturingmachine (AMM); (b) creating an electrolyte using the AMM; and (c) makinga cathode using the AMM. In an embodiment, the anode, the electrolyte,and the cathode are assembled into a fuel cell utilizing the AMM. In anembodiment, the fuel cell is formed using only the AMM. In anembodiment, steps (a), (b), and (c) exclude tape casting and excludescreen printing. In an embodiment, the method excludes compression inassembling. In an embodiment, the layers are deposited one on top ofanother and as such assembling is accomplished at the same time asdeposition. The method of this disclosure is useful in making planarfuel cells. The method of this disclosure is useful in making fuelcells, wherein electrical current flow is perpendicular to theelectrolyte in the lateral direction when the fuel cell is in use.

In an embodiment, the method comprises making at least one barrier layerusing the AMM. In an embodiment, the at least one barrier layer is usedbetween the electrolyte and the cathode or between the electrolyte andthe anode or both. In an embodiment, the at least one barrier layer isassembled with the anode, the electrolyte, and the cathode using theAMM. In an embodiment, no barrier layer is utilized in the fuel cell.

In an embodiment, the method comprises making an interconnect using theAMM. In an embodiment, the interconnect is assembled with the anode, theelectrolyte, and the cathode using the AMM. In an embodiment, the AMMforms a catalyst and incorporates said catalyst into the fuel cell.

In an embodiment, the anode, the electrolyte, the cathode, and theinterconnect are made at a temperature above 100° C. In an embodiment,the method comprises heating the fuel cell, wherein said fuel cellcomprises the anode, the electrolyte, the cathode, the interconnect, andoptionally at least one barrier layer. In an embodiment, the fuel cellcomprises a catalyst. In an embodiment, the method comprises heating thefuel cell to a temperature above 500° C. In an embodiment, the fuel cellis heated using EMR or oven curing.

In an embodiment, the AMM utilizes a multi-nozzle additive manufacturingmethod. In an embodiment, the multi-nozzle additive manufacturing methodcomprises nanoparticle jetting. In an embodiment, a first nozzledelivers a first material. In an embodiment, a second nozzle delivers asecond material. In an embodiment, a third nozzle delivers a thirdmaterial. In an embodiment, particles of a fourth material are placed incontact with a partially constructed fuel cell and bonded to thepartially constructed fuel cell using a laser, photoelectric effect,light, heat, polymerization, or binding. In an embodiment, the anode, orthe cathode, or the electrolyte comprises a first, second, third, orfourth material. In an embodiment, the AMM performs multiple additivemanufacturing techniques. In various embodiments, the additivemanufacturing techniques comprise extrusion, photopolymerization, powderbed fusion, material jetting, binder jetting, directed energydeposition, lamination. In various embodiments, additive manufacturingis a deposition technique comprising material jetting, binder jetting,inkjet printing, aerosol jetting, or aerosol jet printing, vatphotopolymerization, powder bed fusion, material extrusion, directedenergy deposition, sheet lamination, ultrasonic inkjet printing, orcombinations thereof.

Further discussed herein is a method of making a fuel cell stackcomprising (a) producing an anode using an additive manufacturingmachine (AMM); (b) creating an electrolyte using the AMM; (c) making acathode using the AMM; (d) making an interconnect using the AMM; whereinthe anode, the electrolyte, the cathode, and the interconnect form afirst fuel cell; (e) repeating steps (a)-(d) to make a second fuel cell;and (f) assembling the first fuel cell and the second fuel cell into afuel cell stack.

In an embodiment, the first fuel cell and the second fuel cell areformed from the anode, the electrolyte, the cathode, and theinterconnect utilizing the AMM. In an embodiment, the fuel cell stack isformed using only the AMM. In an embodiment, steps (a)-(f) exclude tapecasting and exclude screen printing.

In an embodiment, the method comprises making at least one barrier layerusing the AMM. In an embodiment, the at least one barrier layer is usedbetween the electrolyte and the cathode or between the electrolyte andthe anode or both for the first fuel cell and the second fuel cell.

In an embodiment, steps (a)-(d) are performed at a temperature above100° C. In an embodiment, steps (a)-(d) are performed at a temperaturefrom 100° C. to 500° C. In an embodiment, the AMM makes a catalyst andincorporates said catalyst into the fuel cell stack.

In an embodiment, the method comprises heating the fuel cell stack. Inan embodiment, the method comprises heating the fuel cell stack to atemperature above 500° C. In an embodiment, the fuel cell stack isheated using EMR or oven curing. In an embodiment, the laser has a laserbeam, wherein said laser beam is expanded to create a heating zone withuniform power density. In an embodiment, the laser beam is expanded bythe use of one or more mirrors. In an embodiment, each layer of the fuelcell is EMR cured separately. In an embodiment, a combination of fuelcell layers is EMR cured separately. In an embodiment, the first fuelcell is EMR cured, assembled with the second fuel cell, and then thesecond fuel cell is EMR cured. In an embodiment, the first fuel cell isassembled with the second fuel cell, and then the first fuel cell andthe second fuel cell are EMR cured separately. In an embodiment, thefirst fuel cell and the second fuel cell are EMR cured separately, andthen the first fuel cell is assembled with the second fuel cell to forma fuel cell stack. In an embodiment, the first fuel cell is assembledwith the second fuel cell to form a fuel cell stack, and then the fuelcell stack is EMR cured.

Also discussed herein is a method of making a multiplicity of fuel cellscomprising (a) producing a multiplicity of anodes simultaneously usingan additive manufacturing machine (AMM); (b) creating a multiplicity ofelectrolytes using the AMM simultaneously; and (c) making a multiplicityof cathodes using the AMM simultaneously. In an embodiment, the anodes,the electrolytes, and the cathodes are assembled into fuel cellsutilizing the AMM simultaneously. In an embodiment, the fuel cells areformed using only the AMM.

In an embodiment, the method comprises making at least one barrier layerusing the AMM for each of the multiplicity of fuel cells simultaneously.In an embodiment, said at least one barrier layer is used between theelectrolyte and the cathode or between the electrolyte and the anode orboth. In an embodiment, said at least one barrier layer is assembledwith the anode, the electrolyte, and the cathode using the AMM for eachfuel cell.

In an embodiment, the method comprises making an interconnect using theAMM for each of the multiplicity of fuel cells simultaneously. In anembodiment, said interconnect is assembled with the anode, theelectrolyte, and the cathode using the AMM for each fuel cell. In anembodiment, the AMM forms a catalyst for each of the multiplicity offuel cells simultaneously and incorporates said catalyst into each ofthe fuel cells. In an embodiment, heating of each layer or heating of acombination of layers of the multiplicity of fuel cells takes placesimultaneously. In an embodiment, the multiplicity of fuel cells is 20fuel cells or more.

In an embodiment, the AMM uses different nozzles to jet/print differentmaterials at the same time. For example, in an AMM, a first nozzle makesan anode for fuel cell 1, a second nozzle makes a cathode for fuel cell2, and a third nozzle makes an electrolyte for fuel cell 3, at the sametime. For example, in an AMM, a first nozzle makes an anode for fuelcell 1, a second nozzle makes a cathode for fuel cell 2, a third nozzlemakes an electrolyte for fuel cell 3, and a fourth nozzle makes aninterconnect for fuel cell 4, at the same time.

Disclosed herein is an additive manufacturing machine (AMM) comprising achamber, wherein manufacturing of fuel cells takes place, wherein saidchamber is able to withstand a temperature of at least 300° C. In anembodiment, said chamber enables production of the fuel cells. In anembodiment, said chamber enables heating of the fuel cells in situ. Inan embodiment, said chamber is heated by laser, or electromagneticwaves/electromagnetic radiation (EMR), or hot fluid, or heating elementassociated with the chamber, or combinations thereof. In an embodiment,said heating element comprises a heating surface or a heating coil or aheating rod. In an embodiment, said chamber is configured to applypressure to the fuel cells inside. In an embodiment, the pressure isapplied via a moving element associated with the chamber. In anembodiment, said moving element is a moving stamp or plunger. In anembodiment, said chamber is configured to withstand pressure. In anembodiment, said chamber is configured to be pressurized by a fluid orde-pressurized. In an embodiment, said fluid in the chamber is changedor replaced.

In some cases, the chamber is enclosed. In some cases, the chamber issealed. In some cases, the chamber is open. In some cases, the chamberis a platform without top and side walls.

Referring to FIG. 6, 601 schematically represents deposition nozzles ormaterial jetting nozzles; 602 represents the EMR source, e.g., xenonlamp; 603 represents the object being formed; and 604 represents thechamber as a part of an AMM. As illustrated in FIG. 6, the chamber orreceiver 604 is configured to receive both deposition from nozzles andradiation from an EMR source. In various embodiments, deposition nozzles601 are movable. In various embodiments, the chamber or receiver 604 ismovable. In various embodiments, the EMR source 602 is movable. Invarious embodiments, the object comprises a catalyst, a catalystsupport, a catalyst composite, an anode, a cathode, an electrolyte, anelectrode, an interconnect, a seal, a fuel cell, an electrochemical gasproducer, an electrolyser, an electrochemical compressor, a reactor, aheat exchanger, a vessel, or combinations thereof.

Additive Manufacturing techniques suitable for this disclosure compriseextrusion, photopolymerization, powder bed fusion, material jetting,binder jetting, directed energy deposition, and lamination. In anembodiment, Additive Manufacturing is extrusion additive manufacturing.Extrusion additive manufacturing involves the spatially controlleddeposition of material (e.g., thermoplastics). It is also referred to asfused filament fabrication (FFF) or fused deposition modeling (FDM) inthis disclosure.

In an embodiment, Additive Manufacturing is photopolymerization, i.e.,stereolithography (SLA) for the process of this disclosure. SLA involvesspatially-defined curing of a photoactive liquid (a “photoresin”), usinga scanning laser or a high-resolution projected image, transforming itinto a crosslinked solid. Photopolymerization produces parts withdetails and dimensions ranging from the micrometer- to meter-scales.

In an embodiment, Additive Manufacturing is Powder bed fusion (PBF). PBFAM processes build objects by melting powdered feedstock, such as apolymer or metal. PBF processes begin by spreading a thin layer ofpowder across the build area. Cross sections are then melted a layer ata time, most often using a laser, electron beam, or intense infraredlamps. In an embodiment, PBF of metals is selective laser melting (SLM)or electron beam melting (EBM). In an embodiment, PBF of polymers isselective laser sintering (SLS). In various embodiments, SLS systemsprint thermoplastic polymer materials, polymer composites, or ceramics.In various embodiments, SLM systems are suitable for a variety of puremetals and alloys, wherein the alloys are compatible with the rapidsolidification that occurs in SLM.

In an embodiment, Additive Manufacturing is material jetting. Additivemanufacturing by material jetting is accomplished by depositing smalldrops (or droplets) of material, with spatial control. In variousembodiments, material jetting is performed three dimensionally (3D) ortwo dimensionally (2D) or both. In an embodiment, 3D jetting isaccomplished layer by layer. In an embodiment, print preparationconverts the computer-aided design (CAD), along with specifications ofmaterial composition, color, and other variables to the printinginstructions for each layer. Binder jetting AM involves inkjetdeposition of a liquid binder onto a powder bed. In some cases, binderjetting combines physics of other AM processes: spreading of powder tomake the powder bed (analogous to SLS/SLM), and inkjet printing.

In an embodiment, Additive Manufacturing is directed energy deposition(DED). Instead of using a powder bed as discussed above, the DED processuses a directed flow of powder or a wire feed, along with an energyintensive source such as laser, electric arc, or electron beam. In anembodiment, DED is a direct-write process, wherein the location ofmaterial deposition is determined by movement of the deposition head,which allows large metal structures to be built without the constraintsof a powder bed.

In an embodiment, Additive Manufacturing is Lamination AM, or LaminatedObject Manufacturing (LOM). In an embodiment, consecutive layers ofsheet material are consecutively bonded and cut in order to form a 3Dstructure.

Contrary to traditional methods of manufacturing a fuel cell stack,which can comprise over 100 steps, including but not limited to milling,grinding, filtering, analyzing, mixing, binding, evaporating, aging,drying, extruding, spreading, tape casting, screen printing, stacking,heating, pressing, sintering, and compressing, the method of thisdisclosure manufactures a fuel cell or a fuel cell stack using one AMM.

The AMM of this disclosure preferably performs both extrusion and inkjetting to manufacture a fuel cell or fuel cell stack. Extrusion is usedto manufacture thicker layers of a fuel cell, such as, the anode and/orthe cathode. Ink jetting is used to manufacture thin layers of a fuelcell. Ink jetting is preferably used to form the electrolyte. The AMMoperates at temperature ranges sufficient to enable curing in the AMMitself. Such temperature ranges are 100° C. or above, such as 100°C.-300° C. or 100° C.-500° C.

In the preferred embodiment, all the layers of a fuel cell are formedand assembled via printing. The material for making the anode, thecathode, the electrolyte, and the interconnect, respectively, is madeinto an ink form comprising a solvent and particles (e.g.,nanoparticles). There are two categories of ink formulations—aqueousinks and non-aqueous inks. In some cases, the aqueous ink comprises anaqueous solvent (e.g., water, deionized water), particles, a dispersant,and a surfactant. In some cases, the aqueous ink comprises an aqueoussolvent (e.g., water, deionized water), particles, a dispersant, asurfactant, but no polymeric binder. The aqueous ink optionallycomprises a co-solvent, such as an organic miscible solvent (methanol,ethanol, isopropyl alcohol). Such co-solvents preferably have a lowerboiling point than water. The dispersant is an electrostatic dispersant,a steric dispersant, an ionic dispersant, a non-ionic dispersant, or acombination thereof. The surfactant is preferably non-ionic, such as analcohol alkoxylate, an alcohol ethoxylate. The non-aqueous ink comprisesan organic solvent (e.g., methanol, ethanol, isopropyl alcohol, butanol)and particles.

For example, CGO powder is mixed with water to form an aqueous ink witha dispersant added and a surfactant added but with no polymeric binderadded. The CGO fraction based on mass is in the range of from 10 wt % to25 wt %. For example, CGO powder is mixed with ethanol to form anon-aqueous ink with polyvinyl butaryl added. The CGO fraction based onmass is in the range of from 3 wt % to 30 wt %. For example, LSCF ismixed with n-butanol or ethanol to form a non-aqueous ink with polyvinylbutaryl added. The LSCF fraction based on mass is in the range of from10 wt % to 40 wt %. For example, YSZ particles are mixed with water toform an aqueous ink with a dispersant added and a surfactant added butwith no polymeric binder added. The YSZ fraction based on mass is in therange of from 3 wt % to 40 wt %. For example, NiO particles are mixedwith water to form an aqueous ink with a dispersant added and asurfactant added but with no polymeric binder added. The NiO fractionbased on mass is in the range of from 5 wt % to 25 wt %.

As an example, for the cathode of a fuel cell, LSCF or LSM particles aredissolved in a solvent, wherein the solvent is water or an alcohol(e.g., butanol) or a mixture of alcohols. Organic solvents other thanalcohols may also be used. As an example, LSCF is deposited (e.g.,printed) into a layer. A xenon lamp irradiates the LSCF layer with EMRto sinter the LSCF. The flash lamp is a 10 kW unit applied at a voltageof 400V and a frequency of 10 Hz for a total exposure duration of 1000ms.

For example, for the electrolyte, YSZ particles are mixed with asolvent, wherein the solvent is water (e.g., de-ionized water) (e.g.,de-ionized water) or an alcohol (e.g., butanol) or a mixture ofalcohols. Organic solvents other than alcohols may also be used. For theinterconnect, metallic particles (such as, silver nanoparticles) aredissolved in a solvent, wherein the solvent may include water (e.g.,de-ionized water), organic solvents (e.g. mono-, di-, or tri-ethyleneglycols or higher ethylene glycols, propylene glycol, 1,4-butanediol orethers of such glycols, thiodiglycol, glycerol and ethers and estersthereof, polyglycerol, mono-, di-, and tri-ethanolamine, propanolamine,N,N-dimethylformamide, dimethyl sulfoxide, dimethylacetamide,N-methylpyrrolidone, 1,3-dimethylimidazolidone, methanol, ethanol,isopropanol, n-propanol, diacetone alcohol, acetone, methyl ethylketone, propylene carbonate), and combinations thereof. For a barrierlayer in a fuel cell, CGO particles are dissolved in a solvent, whereinthe solvent is water (e.g., de-ionized water) or an alcohol (e.g.,butanol) or a mixture of alcohols. Organic solvents other than alcoholsmay also be used. CGO is used as barrier layer for LSCF. YSZ may also beused as a barrier layer for LSM. In some cases, for the aqueous inkswhere water is the solvent, no polymeric binder is added to the aqueousinks.

Treatment Process

Herein disclosed is a treatment process that has one or more of thefollowing effects: heating, drying, curing, sintering, annealing,sealing, alloying, evaporating, restructuring, foaming, with sinteringbeing the most preferred process. Preferably, the treatment processcomprises exposing a substrate to a source of electromagnetic radiation(EMR). In an embodiment, the EMR treats a substrate having a firstmaterial. In various embodiments, the EMR has a wavelength ranging from10 to 1500 nm. The wavelengths of the EMR utilized depend on thematerial being sintered. The exposure distance and the slice thicknessare also adjusted to achieve desired printing and sintering results fordifferent materials.

In various embodiments, the EMR has a minimum energy density of 0.1Joule/cm². In an embodiment, the EMR has a burst frequency of 10⁻⁴-1000Hz or 1-1000 Hz or 10-1000 Hz. In an embodiment, the EMR has an exposuredistance of no greater than 50 mm. In an embodiment, the EMR has anexposure duration no less than 0.1 ms or 1 ms. In an embodiment, the EMRis applied with a capacitor voltage of no less than 100V. For example, asingle pulse of EMR is applied with an exposure distance of about 10 mmand an exposure duration of 5-20 ms. For example, multiple pulses of EMRare applied at a burst frequency of 100 Hz with an exposure distance ofabout 10 mm and an exposure duration of 5-20 ms. In an embodiment, theEMR is performed in one exposure. In an embodiment, the EMR is performedin no greater than 10 exposures, or no greater than 100 exposures, or nogreater than 1000 exposures, or no greater than 10,000 exposures.

In various embodiments, metals and ceramics are sintered almostinstantly (milliseconds for <<10 microns) using pulsed light. Thesintering temperature is controlled to be in the range of from 100° C.to 2000° C. The sintering temperature is tailored as a function ofdepth. In one case, the surface temperature is 1000° C. and thesub-surface is kept at 100° C., wherein the sub-surface is 100 micronsbelow the surface. In an embodiment, the material suitable for thistreatment process includes Yttria-stabilized zirconia (YSZ), 8YSZ (8 mol% YSZ powder), Yttirum, Zirconium, gadolinia-doped ceria (GDC or CGO),Samaria-doped ceria (SDC), Scandia-stabilized zirconia (SSZ), Lanthanumstrontium manganite (LSM), Lanthanum Strontium Cobalt Ferrite (LSCF),Lanthanum Strontium Cobaltite (LSC), Lanthanum Strontium GalliumMagnesium Oxide (LSGM), Nickel, NiO, NiO—YSZ, Cu-CGO, Cu₂O, CuO, Cerium,copper, silver, crofer, steel, lanthanum chromite, doped lanthanumchromite, ferritic steel, stainless steel, or combinations thereof.

This treatment process is applicable in the manufacturing process of afuel cell. In an embodiment, a layer of a fuel cell (anode, cathode,electrolyte, seal, catalyst) is treated using the process of thisdisclosure to be heated, cured, sintered, sealed, alloyed, foamed,evaporated, restructured, dried, or annealed. In an embodiment, aportion of a layer of a fuel cell (anode, cathode, electrolyte, seal,catalyst) is treated using the process of this disclosure to be heated,cured, sintered, sealed, alloyed, foamed, evaporated, restructured,dried, or annealed. In an embodiment, a combination of layers of a fuelcell (anode, cathode, electrolyte, seal, catalyst) is treated using theprocess of this disclosure to be heated, cured, sintered, sealed,alloyed, foamed, evaporated, restructured, dried, or annealed, whereinthe layers may be a complete layer or a partial layer. Preferably, thetreatment process is sintering and is accomplished by EMR.

The treatment process of this disclosure is preferably rapid with thetreatment duration varied from microseconds to milliseconds. Thetreatment duration is accurately controlled. The treatment process ofthis disclosure produces fuel cell layers that have no crack or haveminimal cracking. The treatment process of this disclosure controls thepower density or energy density in the treatment volume of the materialbeing treated. The treatment volume is accurately controlled. In anembodiment, the treatment process of this disclosure provides the sameenergy density or different energy densities in a treatment volume. Inan embodiment, the treatment process of this disclosure provides thesame treatment duration or different treatment durations in a treatmentvolume. In an embodiment, the treatment process of this disclosureprovides simultaneous treatment for one or more treatment volumes. In anembodiment, the treatment process of this disclosure providessimultaneous treatment for one or more fuel cell layers or partiallayers or combination of layers. In an embodiment, the treatment volumeis varied by changing the treatment depth.

In an embodiment, a first portion of a treatment volume is treated byelectromagnetic radiation of a first wavelength; a second portion of thetreatment volume is treated by electromagnetic radiation of a secondwavelength. In some cases, the first wavelength is the same as thesecond wavelength. In some cases, the first wavelength is different fromthe second wavelength. In an embodiment, the first portion of atreatment volume has a different energy density from the second portionof the treatment volume. In an embodiment, the first portion of atreatment volume has a different treatment duration from the secondportion of the treatment volume.

In an embodiment, the EMR has a broad emission spectrum so that thedesired effects are achieved for a wide range of materials havingdifferent absorption characteristics. In this disclosure, absorption ofelectromagnetic radiation (EMR) refers to the process, wherein theenergy of a photon is taken up by matter, such as the electrons of anatom. Thus, the electromagnetic energy is transformed into internalenergy of the absorber, for example, thermal energy. For example, theEMR spectrum extends from the deep ultraviolet (UV) range to the nearinfrared (IR) range, with peak pulse powers at 220 nm wavelength. Thepower of such EMR is on the order of Megawatts. Such EMR sources performtasks such as breaking chemical bonds, sintering, ablating orsterilizing.

In an embodiment, the EMR has an energy density of no less than 0.1, 1,or 10 Joule/cm². In an embodiment, the EMR has a power output of no lessthan 1 watt (W), 10 W, 100 W, 1000 W. The EMR delivers power to thesubstrate of no less than 1 W, 10 W, 100 W, or 1000 W. In an embodiment,such EMR exposure heats the material in the substrate. In an embodiment,the EMR has a range or a spectrum of different wavelengths. In variousembodiments, the treated substrate is at least a portion of an anode,cathode, electrolyte, catalyst, barrier layer, or interconnect of a fuelcell.

In an embodiment, the peak wavelength of the EMR is between 50 and 550nm or between 100 and 300 nm. In an embodiment, the wavelength of theEMR is between 50 and 550 nm or between 100 and 300 nm. In anembodiment, the absorption of at least a portion of the substrate for atleast one frequency of the EMR between 10 and 1500 nm is no less than30% or no less than 50%. In an embodiment, the absorption of at least aportion of the substrate for at least one frequency between 50 and 550nm is no less than 30% or no less than 50%. In an embodiment, theabsorption of at least a portion of the substrate for at least onefrequency between 100 and 300 nm is no less than 30% or no less than50%.

Sintering is the process of compacting and forming a solid mass ofmaterial by heat or pressure without melting it to the point ofliquefaction. In this disclosure, the substrate under EMR exposure issintered but not melted. In an embodiment, the EMR is UV light, nearultraviolet light, near infrared light, infrared light, visible light,laser, electron beam, microwave. In an embodiment, the substrate isexposed to the EMR for no less than 1 microsecond, no less than 1millisecond. In an embodiment, the substrate is exposed to the EMR forless than 1 second at a time or less than 10 seconds at a time. In anembodiment, the substrate is exposed to the EMR for less than 1 secondor less than 10 seconds. In an embodiment, the substrate is exposed tothe EMR repeatedly, for example, more than 1 time, more than 3 times,more than 10 times. In an embodiment, the substrate is distanced fromthe source of the EMR for less than 50 cm, less than 10 cm, less than 1cm, or less than 1 mm.

In an embodiment, after EMR exposure, a second material is added to orplaced on to the first material. In various cases, the second materialis the same as the first material. In an embodiment, the second materialis exposed to the EMR. In some cases, a third material is added. In anembodiment, the third material is exposed to the EMR.

In an embodiment, the first material comprises YSZ, 8YSZ, Yttirum,Zirconium, GDC, SDC, LSM, LSCF, LSC, Nickel, NiO, Cerium. In anembodiment, the second material comprises graphite. In an embodiment,the electrolyte, anode, or cathode comprises a second material. In somecases, the volume fraction of the second material in the electrolyte,anode, or cathode is less than 20%, 10%, 3%, or 1%. The absorption rateof the second material for at least one frequency (e.g., between 10 and1500 nm or between 100 and 300 nm or between 50 and 550 nm) is greaterthan 30% or greater than 50%.

In various embodiments, one or a combination of parameters arecontrolled, wherein such parameters include distance between the EMRsource and the substrate, the energy density of the EMR, the spectrum ofthe EMR, the voltage of the EMR, the duration of exposure, the burstfrequency, and the number of EMR exposures. Preferably, these parametersare controlled to minimize the formation of cracks in the substrate.

In an embodiment, the EMR energy is delivered to a surface area of noless than 1 mm², or no less than 1 cm², or no less than 10 cm², or noless than 100 cm². In some cases, during EMR exposure of the firstmaterial, at least a portion of an adjacent material is heated at leastin part by conduction of heat from the first material. In variousembodiments, the layers of the fuel cell (e.g., anode, cathode,electrolyte) are thin. Preferably, they are no greater than 30 microns,no greater than 10 microns, or no greater than 1 micron.

In an embodiment, the first material of the substrate is in the form ofa powder, sol gel, colloidal suspension, hybrid solution, or sinteredmaterial. In various embodiments, the second material may be added byvapor deposition. In an embodiment, the second material coats the firstmaterial. In an embodiment, the second material reacts with light, e.g.focused light, as by a laser, and sinters or anneals with the firstmaterial.

Advantages

The preferred treatment process of this disclosure enables rapidmanufacturing of fuel cells by eliminating traditional, costly, timeconsuming, expensive sintering processes and replacing them with rapid,in-situ methods that allow continuous manufacturing of the layers of afuel cell in a single machine if desired. This process also shortenssintering time from hours and days to seconds or milliseconds or evenmicroseconds.

In various embodiments, this treatment method is used in combinationwith manufacturing techniques like screen printing, tape casting,spraying, sputtering, physical vapor deposition, and additivemanufacturing.

This preferred treatment method enables tailored and controlled heatingby tuning EMR characteristics (such as, wavelengths, energy density,burst frequency, and exposure duration) combined with controllingthicknesses of the layers of the substrate and heat conduction intoadjacent layers to allow each layer to sinter, anneal, or cure at eachdesired target temperature. This process enables more uniform energyapplication, decreases or eliminates cracking, which improveselectrolyte performance. The substrate treated with this preferredprocess also has less thermal stress due to more uniform heating.

Integrated Deposition and Heating

The preferred method comprises depositing a composition on a substrateslice by slice to form an object; heating in situ the object usingelectromagnetic radiation (EMR); wherein said composition comprises afirst material and a second material, wherein the second material has ahigher absorbance of the radiation than the first material. In variousembodiments, heating causes an effect comprising drying, curing,sintering, annealing, sealing, alloying, evaporating, restructuring,foaming, or combinations thereof. The preferred effect is sintering. Inan embodiment, the EMR has a wavelength ranging from 10 to 1500 nm andthe EMR has a minimum energy density of 0.1 Joule/cm². In an embodiment,peak wavelength is on the basis of relative irradiance with respect towavelength. In an embodiment, the EMR comprises UV light, nearultraviolet light, near infrared light, infrared light, visible light,laser, electron beam.

FIG. 6 illustrates an object on a substrate formed by deposition nozzlesand EMR for heating in situ, according to the preferred embodiment ofthis disclosure.

In an embodiment, the first material comprises YSZ, SSZ, CGO, SDC,NiO—YSZ, LSM-YSZ, CGO-LSCF, doped lanthanum chromite, stainless steel,or combinations thereof. In an embodiment, the second material comprisescarbon, nickel oxide, nickel, silver, copper, CGO, SDC, NiO—YSZ,NiO—SSZ, LSCF, LSM, doped lanthanum chromite ferritic steels, orcombinations thereof. In an embodiment, said object comprises acatalyst, a catalyst support, a catalyst composite, an anode, a cathode,an electrolyte, an electrode, an interconnect, a seal, a fuel cell, anelectrochemical gas producer, an electrolyser, an electrochemicalcompressor, a reactor, a heat exchanger, a vessel, or combinationsthereof.

In the preferred embodiment, the second material is a deposited in thesame slice as the first material. In an alternative embodiment, thesecond material is a deposited in a slice adjacent another slice thatcontains the first material. In an embodiment, said heating removes atleast a portion of the second material. In an embodiment, said removingleaves minimal residue of the portion of the second material.Preferably, this step leaves minimal residue of the portion of thesecond material, which is to say that there is no significant residuethat would interfere with the subsequent steps in the process or theoperation of the device being constructed. More preferably, this leavesno measurable reside of the second material.

In an embodiment, the second material adds thermal energy to the firstmaterial during heating. In an embodiment, the second material has aradiation absorption that is at least 5 times that of the firstmaterial; preferably the second material has a radiation absorption thatis at least 10 times that of the first material; more preferably thesecond material has a radiation absorption that is at least 50 timesthat of the first material; most preferably the second material has aradiation absorption that is at least 100 times that of the firstmaterial.

In an embodiment, the second material has a peak absorbance wavelengthno less than 200 nm, or no less than 250 nm, or no less than 300 nm, orno less than 400 nm, or no less than 500 nm. In an embodiment, the firstmaterial has a peak absorbance wavelength no greater than 700 nm, or nogreater than 600 nm, or no greater than 500 nm, or no greater than 400nm, or no greater than 300 nm. In an embodiment, the EMR has awavelength no less than 200 nm, or no less than 250 nm, or no less than300 nm, or no less than 400 nm, or no less than 500 nm. In anembodiment, the second material comprises carbon, nickel oxide, nickel,silver, copper, CGO, NiO—YSZ, LSCF, LSM, ferritic steels, orcombinations thereof. In some cases, the ferritic steel is Crofer 22APU. Preferably, the second material is carbon and is in the form ofgraphite, graphene, carbon nanoparticles, nano diamonds, or combinationsthereof. Most preferably, the carbon is in the form of graphiteparticles.

In an embodiment, the depositing is accomplished by material jetting,binder jetting, inkjet printing, aerosol jetting, or aerosol jetprinting, vat photopolymerization, powder bed fusion, materialextrusion, directed energy deposition, sheet lamination, ultrasonicinkjet printing, or combinations thereof.

In an embodiment, the depositing is manipulated by controlling thedistance from the EMR to the substrate, the EMR energy density, the EMRspectrum, the EMR voltage, the EMR exposure duration, the EMR exposurearea, the EMR exposure volume, the EMR burst frequency, the EMR exposurerepetition number, and combinations thereof. Preferably, the object doesnot change location between depositing and heating. In an embodiment,the EMR has a power output of no less than 1 W, or 10 W, or 100 W, or1000 W.

Herein also disclosed is a system comprising at least one depositionnozzle, an electromagnetic radiation (EMR) source, and a depositionreceiver, wherein the deposition receiver is configured to receive EMRexposure and deposition at the same location. In some cases, thereceiver is configured such that it receives deposition for a first timeperiod, moves to a different location in the system to receive EMRexposure for a second time period.

The following detailed discussion takes the production of solid oxidefuel cells (SOFCs) as an example. As one in the art recognizes, themethodology and the manufacturing process are applicable to all fuelcell types. As such, the production of all fuel cell types is within thescope of this disclosure.

Fuel Cell

A fuel cell is an electrochemical apparatus that converts the chemicalenergy from a fuel into electricity through an electrochemical reaction.As mentioned above, there are many types of fuel cells, e.g.,proton-exchange membrane fuel cells (PEMFCs), solid oxide fuel cells(SOFCs). A fuel cell typically comprises an anode, a cathode, anelectrolyte, an interconnect, optionally a barrier layer and/oroptionally a catalyst. Both the anode and the cathode are electrodes.

FIGS. 1-5 illustrate various embodiments of the components in a fuelcell or a fuel cell stack. In these embodiments, the anode, cathode,electrolyte, and interconnect are cuboids or rectangular prisms.

Referring to FIG. 1, 101 schematically represents the anode; 102represents the cathode; and 103 represents the electrolyte.

Referring to FIG. 2, 201 schematically represents the anode; 202represents the cathode; 203 represents the electrolyte; and 204represents the barrier layers.

Referring to FIG. 3, 301 schematically represents the anode; 302represents the cathode; 303 represents the electrolyte; 304 representsthe barrier layers; and 305 represents the catalyst.

Referring to FIG. 4, 401 schematically represents the anode; 402represents the cathode; 403 represents the electrolyte; 404 representsthe barrier layers; 405 represents the catalyst; and 406 represents theinterconnect.

Referring to FIG. 5, 501 schematically represents the anode; 502represents the cathode; 503 represents the electrolyte; 504 representsthe barrier layers; 505 represents the catalyst; and 506 represents theinterconnect. Two fuel cell repeat units or two fuel cells form a stackas illustrated in FIG. 5. As is seen, on one side, the interconnect isin contact with the largest surface of the cathode of the top fuel cell(or fuel cell repeat unit) and on the opposite side the interconnect isin contact with the largest surface of the catalyst (optional) or theanode of the bottom fuel cell (or fuel cell repeat unit). These repeatunits or fuel cells are connected in parallel by being stacked atop oneanother and sharing an interconnect in between via direct contact withthe interconnect rather than via electrical wiring. This kind ofconfiguration is in contrast to segmented-in-series (SIS) type fuelcells.

The listings of material for the electrodes, the electrolyte, and theinterconnect in a fuel cell are exemplary and not limiting. Thedesignations of anode material and cathode material are also notlimiting because the function of the material during operation (e.g.,whether it is oxidizing or reducing) determines whether the material isused as an anode or a cathode.

Cathode

In an embodiment, the cathode comprises perovskites, such as LSC, LSCF,LSM. In an embodiment, the cathode comprises lanthanum, cobalt,strontium, manganite. In an embodiment, the cathode is porous. In anembodiment, the cathode comprises YSZ, Nitrogen, Nitrogen Boron dopedGraphene, La0.6Sr0.4Co0.2Fe0.8O3, SrCo0.5Sc0.5O3, BaFe0.75Ta0.25O3,BaFe0.875Re0.125O3, Ba0.5La0.125Zn0.375NiO3,Ba0.75Sr0.25Fe0.875Ga0.125O3, BaFe0.125Co0.125, Zr0.75O3. In anembodiment, the cathode comprises LSCo, LCo, LSF, LSCoF. In anembodiment, the cathode comprises perovskites LaCoO3, LaFeO3, LaMnO3,(La,Sr)MnO3, LSM-GDC, LSCF-GDC, LSC-GDC. Cathodes containing LSCF aresuitable for intermediate-temperature fuel cell operation.

In an embodiment, the cathode comprises a material selected from thegroup consisting of lanthanum strontium manganite, lanthanum strontiumferrite, and lanthanum strontium cobalt ferrite. In an embodiment, thecathode comprises lanthanum strontium manganite.

Anode

In an embodiment, the anode comprises Copper, Nickle-Oxide,Nickle-Oxide-YSZ, NiO-GDC, NiO-SDC, Aluminum doped Zinc Oxide,Molybdenum Oxide, Lanthanum, strontium, chromite, ceria, perovskites(such as, LSCF [La{1-x}Sr{x}Co{1-y}Fe{y}O3] or LSM [La{1-x}Sr{x}MnO3],where x is usually 0.15-0.2 and y is 0.7 to 0.8). In an embodiment, theanode comprises SDC or BZCYYb coating or barrier layer to reduce cokingand sulfur poisoning. In an embodiment, the anode is porous. In anembodiment, the anode comprises combination of electrolyte material andelectrochemically active material, combination of electrolyte materialand electrically conductive material.

In an embodiment, the anode comprises nickel and yttria stabilizedzirconia. In an embodiment, the anode is formed by reduction of amaterial comprising nickel oxide and yttria stabilized zirconia. In anembodiment, the anode comprises nickel and gadolinium stabilized ceria.In an embodiment, the anode is formed by reduction of a materialcomprising nickel oxide and gadolinium stabilized ceria.

Electrolyte

In an embodiment, the electrolyte in a fuel cell comprises stabilizedzirconia e.g., YSZ, YSZ-8, Y0.16Zr0.84O2. In an embodiment, theelectrolyte comprises doped LaGaO3, e.g., LSGM, La0.9Sr0.1Ga0.8Mg0.2O3.In an embodiment, the electrolyte comprises doped ceria, e.g., GDC,Gd0.2Ce0.8O2. In an embodiment, the electrolyte comprises stabilizedbismuth oxide e.g., BVCO, Bi2V0.9Cu0.1O5.35.

In an embodiment, the electrolyte comprises zirconium oxide, yttriastabilized zirconium oxide (also known as YSZ, YSZ8 (8 mole % YSZ)),ceria, gadolinia, scandia, magnesia, calcia. In an embodiment, theelectrolyte is sufficiently impermeable to prevent significant gastransport and prevent significant electrical conduction; and allow ionconductivity. In an embodiment, the electrolyte comprises doped oxidesuch as cerium oxide, yttrium oxide, bismuth oxide, lead oxide,lanthanum oxide. In an embodiment, the electrolyte comprises perovskite,such as, LaCoFeO3 or LaCoO3 or Ce0.9Gd0.1O2 (GDC) or Ce0.9Sm0.1O2 (SDC,samaria doped ceria) or scandia stabilized zirconia.

In an embodiment, the electrolyte comprises a material selected from thegroup consisting of zirconia, ceria, and gallia. In an embodiment, thematerial is stabilized with a stabilizing material selected from thegroup consisting of scandium, samarium, gadolinium, and yttrium. In anembodiment, the material comprises yttria stabilized zirconia.

Interconnect

In an embodiment, the interconnect comprises silver, gold, platinum,AISI441, ferritic stainless steel, stainless steel, Lanthanum, Chromium,Chromium Oxide, Chromite, Cobalt, Cesium, Cr2O3. In an embodiment, theanode comprises LaCrO3 coating on Cr2O3 or NiCo2O4 or MnCo2O4 coatings.In an embodiment, the interconnect surface is coated with Cobalt and/orCesium. In an embodiment, the interconnect comprises ceramics. In anembodiment, the interconnect comprises Lanthanum Chromite or dopedLanthanum Chromite. In an embodiment, the interconnect is made of amaterial comprising metal, stainless steel, ferritic steel, crofer,lanthanum chromite, silver, metal alloys, nickel, nickel oxide,ceramics, or graphene.

Catalyst

In various embodiments, the fuel cell comprises a catalyst, such as,platinum, palladium, scandia, chromium, cobalt, cesium, CeO2, nickle,nickle oxide, zine, copper, titantia, ruthenium, rhodiu, MoS2,molybdenum, rhenium, vandia, manganese, magnesium, iron. In variousembodiments, the catalyst promotes methane reforming reactions togenerate hydrogen and carbon monoxide for them to be oxidized in thefuel cell. Very often, the catalyst is part of the anode, especiallynickel anode has inherent methane reforming properties. In anembodiment, the catalyst is between 1%-5%, or 0.1% to 10% by mass. In anembodiment, the catalyst is used on the anode surface or in the anode.In various embodiments, such anode catalysts reduce harmful cokingreactions and carbon deposits. In various embodiments, simple oxideversion of catalysts is used or perovskite. For example, 2% mass CeO2catalyst is used for methane-powered fuel cells. In various embodiments,the catalyst is dipped or coated on the anode. In various embodiments,the catalyst is made by an additive manufacturing machine (AMM) andincorporated into the fuel cell using the AMM.

The unique manufacturing methods as discussed herein have allowed themaking of ultra-thin fuel cells and fuel cell stacks. Conventionally, toachieve structural integrity, the fuel cell has at least one thick layerper repeat unit, like the anode (an anode-supported fuel cell) or theinterconnect (an interconnect-supported fuel cell). As discussed above,the pressing or compression step is typically necessary to assemble thefuel cell components to achieve gas tightness and/or proper electricalcontact in traditional manufacturing processes. As such, the thicklayers are necessary not only because traditional methods (like tapecasting) cannot produce ultra-thin layers but also because the layershave to be thick to endure the pressing or compression step. Thepreferred manufacturing methods of this disclosure have eliminated theneed for pressing or compression. The preferred manufacturing methods ofthis disclosure have also enabled the making of ultra-thin layers. Themultiplicity of the layers in a fuel cell or a fuel cell stack providessufficient structural integrity for proper operation when they are madeaccording to this disclosure.

Herein disclosed is a fuel cell comprising an anode no greater than 1 mmor 500 microns or 300 microns or 100 microns or 50 microns or no greaterthan 25 microns in thickness, a cathode no greater than 1 mm or 500microns or 300 microns or 100 microns or 50 microns or no greater than25 microns in thickness, and an electrolyte no greater than 1 mm or 500microns or 300 microns or 100 microns or 50 microns or 30 microns inthickness. In an embodiment, the fuel cell comprises an interconnecthaving a thickness of no less than 50 microns. In some cases, a fuelcell comprises an anode no greater than 25 microns in thickness, acathode no greater than 25 microns in thickness, and an electrolyte nogreater than 10 microns or 5 microns in thickness. In an embodiment, thefuel cell comprises an interconnect having a thickness of no less than50 microns. In an embodiment, the interconnect has a thickness of from50 microns to 5 cm.

In a preferred embodiment, the fuel cell comprises an anode no greaterthan 100 microns in thickness, a cathode no greater than 100 microns inthickness, an electrolyte no greater than 20 microns in thickness, andan interconnect no greater than 30 microns in thickness. In a morepreferred embodiment, a fuel cell comprises an anode no greater than 50microns in thickness, a cathode no greater than 50 microns in thickness,an electrolyte no greater than 10 microns in thickness, and aninterconnect no greater than 25 microns in thickness. In an embodiment,the interconnect has a thickness in the range of from 1 micron to 20microns.

In the preferred embodiment, the fuel cell comprises a barrier layerbetween the anode and the electrolyte, or a barrier layer between thecathode and the electrolyte, or both barrier layers. In some cases, thebarrier layers are the interconnects. In such cases, the reactants aredirectly injected into the anode and the cathode.

In an embodiment, the cathode has a thickness of no greater than 15microns, or no greater than 10 microns, or no greater than 5 microns. Inan embodiment, the anode has a thickness of no greater than 15 microns,or no greater than 10 microns, or no greater than 5 microns. In anembodiment, the electrolyte has a thickness of no greater than 5microns, or no greater than 2 microns, or no greater than 1 micron, orno greater than 0.5 micron. In an embodiment, the interconnect is madeof a material comprising metal, stainless steel, silver, metal alloys,nickel, nickel oxide, ceramics, or graphene. In an embodiment, the fuelcell has a total thickness of no less than 1 micron.

Also discussed herein is a fuel cell stack comprising a multiplicity offuel cells, wherein each fuel cell comprises an anode no greater than 25microns in thickness, a cathode no greater than 25 microns in thickness,an electrolyte no greater than 10 microns in thickness, and aninterconnect having a thickness of from 100 nm to 100 microns. In anembodiment, each fuel cell comprises a barrier layer between the anodeand the electrolyte, or a barrier layer between the cathode and theelectrolyte, or both barrier layers. In an embodiment, the barrierlayers are the interconnects. For example, the interconnect is made ofsilver. For example, the interconnect has a thickness of from 500 nm to1000 nm. In an embodiment, the interconnect is made of a materialcomprising metal, stainless steel, silver, metal alloys, nickel, nickeloxide, ceramics, or graphene.

In an embodiment, the cathode has a thickness of no greater than 15microns, or no greater than 10 microns, or no greater than 5 microns. Inan embodiment, the anode has a thickness of no greater than 15 microns,or no greater than 10 microns, or no greater than 5 microns. In anembodiment, the electrolyte has a thickness of no greater than 5microns, or no greater than 2 microns, or no greater than 1 micron, orno greater than 0.5 micron. In an embodiment, each fuel cell has a totalthickness of no less than 1 micron.

Further discussed herein is a method of making a fuel cell comprising(a) forming an anode no greater than 25 microns in thickness, (b)forming a cathode no greater than 25 microns in thickness, and (c)forming an electrolyte no greater than 10 microns in thickness. In anembodiment, steps (a)-(c) are performed using additive manufacturing. Invarious embodiments, said additive manufacturing uses extrusion,photopolymerization, powder bed fusion, material jetting, binderjetting, directed energy deposition, or lamination.

In an embodiment, the method comprises assembling the anode, thecathode, and the electrolyte using additive manufacturing. In anembodiment, the method comprises forming an interconnect and assemblingthe interconnect with the anode, the cathode, and the electrolyte.

In an embodiment, the method comprises making at least one barrierlayer. In an embodiment, said at least one barrier layer is used betweenthe electrolyte and the cathode or between the electrolyte and the anodeor both. In an embodiment, said at least one barrier layer is also aninterconnect.

In an embodiment, the method comprises heating the fuel cell such thatshrinkage rates of the anode, the cathode, and the electrolyte arematched. In an embodiment, such heating takes place for no greater than30 minutes, preferably no greater than 30 seconds, and most preferablyno greater than 30 milliseconds. In this disclosure, matching shrinkagerates during heating is discussed in detail below (matching SRTs). Whena fuel cell comprises a first composition and a second composition,wherein the first composition has a first shrinkage rate and the secondcomposition has a second shrinkage rate, the heating described in thisdisclosure preferably takes place such that the difference between thefirst shrinkage rate and the second shrinkage rate is no greater than75% of the first shrinkage rate.

In the preferred embodiment, the heating makes use of electromagneticradiation (EMR). In various embodiments, EMR comprises UV light, nearultraviolet light, near infrared light, infrared light, visible light,laser, electron beam. Preferably, heating is performed in situ, namelyin the same machine and in the same location in that machine as thelayers are deposited.

Also disclosed herein is a method of making a fuel cell stack comprisinga multiplicity of fuel cells, the method comprising (a) forming an anodeno greater than 25 microns in thickness in each fuel cell, (b) forming acathode no greater than 25 microns in thickness in each fuel cell, (c)forming an electrolyte no greater than 10 microns in thickness in eachfuel cell, and (d) producing an interconnect having a thickness of from100 nm to 100 microns in each fuel cell.

In an embodiment, steps (a)-(d) are performed using additivemanufacturing. In various embodiments, said additive manufacturing usesextrusion, photopolymerization, powder bed fusion, material jetting,binder jetting, directed energy deposition, and/or lamination.

In an embodiment, the method comprises assembling the anode, thecathode, the electrolyte, and the interconnect using additivemanufacturing. In an embodiment, the method comprises making at leastone barrier layer in each fuel cell. In an embodiment, said at least onebarrier layer is used between the electrolyte and the cathode or betweenthe electrolyte and the anode or both. In an embodiment, said at leastone barrier layer is the interconnect.

In an embodiment, the method comprises heating each fuel cell such thatshrinkage rates of the anode, the cathode, and the electrolyte arematched. In an embodiment, such heating takes place for no greater than30 minutes, or no greater than 30 seconds, or no greater than 30milliseconds. In an embodiment, said heating comprises electromagneticradiation (EMR). In various embodiments, EMR comprises UV light, nearultraviolet light, near infrared light, infrared light, visible light,laser, electron beam. In an embodiment, heating is performed in situ.

In an embodiment, the method comprises heating the entire fuel cellstack such that shrinkage rates of the anode, the cathode, and theelectrolyte are matched. In an embodiment, such heating takes place forno greater than 30 minutes, or no greater than 30 seconds, or no greaterthan 30 milliseconds.

Herein discussed is a method of making an electrolyte comprising (a)formulating a colloidal suspension, wherein the colloidal suspensioncomprises an additive, particles having a range of diameters and a sizedistribution, and a solvent; (b) forming an electrolyte comprising thecolloidal suspension; and (c) heating at least a portion of theelectrolyte; wherein formulating the colloidal suspension is preferablyoptimized by controlling the pH of the colloidal suspension, orconcentration of the binder in the colloidal suspension, or compositionof the binder in the colloidal suspension, or the range of diameters ofthe particles, or maximum diameter of the particles, or median diameterof the particles, or the size distribution of the particles, or boilingpoint of the solvent, or surface tension of the solvent, or compositionof the solvent, or thickness of the minimum dimension of theelectrolyte, or the composition of the particles, or combinationsthereof.

Herein discussed is a method of making a fuel cell comprising (a)obtaining a cathode and an anode; (b) modifying the cathode surface andthe anode surface; (c) formulating a colloidal suspension, wherein thecolloidal suspension comprises an additive, particles having a range ofdiameters and a size distribution, and a solvent; (d) forming anelectrolyte comprising the colloidal suspension between the modifiedanode surface and the modified cathode surface; and (e) heating at leasta portion of the electrolyte; wherein formulating the colloidalsuspension comprises controlling pH of the colloidal suspension, orconcentration of the binder in the colloidal suspension, or compositionof the binder in the colloidal suspension, or the range of diameters ofthe particles, or maximum diameter of the particles, or median diameterof the particles, or the size distribution of the particles, or boilingpoint of the solvent, or surface tension of the solvent, or compositionof the solvent, or thickness of the minimum dimension of theelectrolyte, or the composition of the particles, or combinationsthereof. In various embodiments, the anode and the cathode are obtainedvia any suitable means. In an embodiment, the modified anode surface andthe modified cathode surface have a maximum height profile roughnessthat is less than the average diameter of the particles in the colloidalsuspension. The maximum height profile roughness refers to the maximumdistance between any trough and an adjacent peak as illustrated in FIG.9. In various embodiments, the anode surface and the cathode surface aremodified via any suitable means.

Further disclosed herein is a method of making a fuel cell comprising(a) obtaining a cathode and an anode; (b) formulating a colloidalsuspension, wherein the colloidal suspension comprises an additive,particles having a range of diameters and a size distribution, and asolvent; (c) forming an electrolyte comprising the colloidal suspensionbetween the anode and the cathode; and (d) heating at least a portion ofthe electrolyte; wherein formulating the colloidal suspension comprisescontrolling pH of the colloidal suspension, or concentration of thebinder in the colloidal suspension, or composition of the binder in thecolloidal suspension, or the range of diameters of the particles, ormaximum diameter of the particles, or median diameter of the particles,or the size distribution of the particles, or boiling point of thesolvent, or surface tension of the solvent, or composition of thesolvent, or thickness of the minimum dimension of the electrolyte, orthe composition of the particles, or combinations thereof. In variousembodiments, the anode and the cathode are obtained via any suitablemeans. In an embodiment, the anode surface in contact with theelectrolyte and the cathode surface in contact with the electrolyte havea maximum height profile roughness that is less than the averagediameter of the particles in the colloidal suspension.

In an embodiment, the solvent comprises water. In an embodiment, thesolvent comprises an organic component. In an embodiment, the solventcomprises ethanol, butanol, alcohol, terpineol, Diethyl ether1,2-Dimethoxyethane (DME (ethylene glycol dimethyl ether), 1-Propanol(n-propanol, n-propyl alcohol), or butyl alcohol. In an embodiment, thesolvent surface tension is less than half of water's surface tension inair. In an embodiment, the solvent surface tension is less than 30 mN/mat atmospheric conditions.

In an embodiment, the electrolyte is formed adjacent to a firstsubstrate. In an embodiment, the electrolyte is formed between a firstsubstrate and a second substrate. In an embodiment, the first substratehas a maximum height profile roughness that is less than the averagediameter of the particles. In an embodiment, the particles have apacking density greater than 40%, or greater than 50%, or greater than60%. In an embodiment, the particles have a packing density close to therandom close packing (RCP) density.

Random close packing (RCP) is an empirical parameter used tocharacterize the maximum volume fraction of solid objects obtained whenthey are packed randomly. A container is randomly filled with objects,and then the container is shaken or tapped until the objects do notcompact any further, at this point the packing state is RCP. The packingfraction is the volume taken by number of particles in a given space ofvolume. The packing fraction determines the packing density. Forexample, when a solid container is filled with grain, shaking thecontainer will reduce the volume taken up by the objects, thus allowingmore grain to be added to the container. Shaking increases the densityof packed objects. When shaking no longer increases the packing density,a limit is reached and if this limit is reached without obvious packinginto a regular crystal lattice, this is the empirical randomclose-packed density.

In an embodiment, the median particle diameter is preferably between 50nm and 1000 nm, or between 100 nm and 500 nm, or approximately 200 nm.In an embodiment, the first substrate comprises particles having amedian particle diameter, wherein the median particle diameter of theelectrolyte is no greater than 10 times and no less than 1/10 of themedian particle diameter of the first substrate. In an embodiment, thefirst substrate comprises a particle size distribution that is bimodal,i.e. having a first mode and a second mode, each having a medianparticle diameter. In an embodiment, the median particle diameter in thefirst mode of the first substrate is greater than 2 times, or greaterthan 5 times, or greater than 10 times that of the second mode. In anembodiment, the particle size distribution of the first substrate isadjusted to change the behavior of the first substrate during heating.In an embodiment, the first substrate has a shrinkage that is a functionof heating temperature. In an embodiment, the particles in the colloidalsuspension has a maximum particle diameter and a minimum particlediameter, wherein the maximum particle diameter is less than 2 times, orless than 3 times, or less than 5 times, or less than 10 times theminimum particle diameter. In an embodiment, the minimum dimension ofthe electrolyte is less than 10 microns, or less than 2 microns, or lessthan 1 micron, or less than 500 nm.

In an embodiment, the electrolyte has a gas permeability of no greaterthan 1 millidarcy, preferably no greater than 100 microdarcy, and mostpreferably no greater than 1 microdarcy. Preferably, the electrolyte hasno cracks penetrating through the minimum dimension of the electrolyte.In an embodiment, the boiling point of the solvent is no less than 200°C., or no less than 100° C., or no less than 75° C. In an embodiment,the boiling point of the solvent is no greater than 125° C., or nogreater than 100° C., or no greater than 85° C., no greater than 70° C.In an embodiment, the pH of the colloidal suspension is no less than 7,or no less than 9, or no less than 10.

In an embodiment, the additive comprises polyethylene glycol (PEG),ethyl cellulose, polyvinylpyrrolidone (PVP), polyvinyl butyral (PVB),butyl benzyl phthalate (BBP), polyalkalyne glycol (PAG). In anembodiment, the additive concentration is no greater than 100 mg/cm3, orno greater than 50 mg/cm3, or no greater than 30 mg/cm3, or no greaterthan 25 mg/cm3.

In an embodiment, the colloidal suspension is milled. In an embodiment,the colloidal suspension is milled using a rotational mill. In anembodiment, the rotational mill is operated at no less than 20 rpm, orno less than 50 rpm, or no less than 100 rpm, or no less than 150 rpm.In an embodiment, the colloidal suspension is milled using zirconiamilling balls or tungsten carbide balls. In an embodiment, the colloidalsuspension is milled for no less than 2 hours, or no less than 4 hours,or no less than 1 day, or no less than 10 days.

In an embodiment, the particle concentration in the colloidal suspensionis no greater than 30 wt %, or no greater than 20 wt %, or no greaterthan 10 wt %. In an embodiment, the particle concentration in thecolloidal suspension is no less than 2 wt %. In an embodiment, theparticle concentration in the colloidal suspension is no greater than 10vol %, or no greater than 5 vol %, or no greater than 3 vol %, or nogreater than 1 vol %. In an embodiment, the particle concentration inthe colloidal suspension is no less than 0.1 vol %.

In an embodiment, the electrolyte is formed using an additivemanufacturing machine (AMM). In an embodiment, the first substrate isformed using an AMM. In an embodiment, said heating comprises the use ofelectromagnetic radiation (EMR). In an embodiment, the EMR comprises UVlight, near ultraviolet light, near infrared light, infrared light,visible light, laser. In an embodiment, the first substrate and theelectrolyte are heated to cause co-sintering. In an embodiment, thefirst substrate, the second substrate, and the electrolyte are heated tocause co-sintering. In an embodiment, the EMR is controlled topreferentially sinter the first substrate over the electrolyte.

In an embodiment, the electrolyte is in compression throughout itsthickness after heating. In an embodiment, the first substrate and thesecond substrate apply compressive stress to the electrolyte afterheating. In an embodiment, the first substrate and the second substrateare anode and cathode of a fuel cell. In an embodiment, the minimumdimension of the electrolyte is between 500 nm and 5 microns. In anembodiment, the minimum dimension of the electrolyte is between 1 micronand 2 microns.

The detailed discussion herein is generally directed to the productionof solid oxide fuel cells (SOFCs) as an example. As one in the artrecognizes, the methodology and the manufacturing process are applicableto all fuel cell types. As such, the production of all fuel cell typesare within the scope of this disclosure.

Fuel Cell Cartridge

In various embodiments, the fuel cell stack is configured to be madeinto a cartridge form, such as an easily detachable flanged fuel cellcartridge (FCC) design.

Referring to FIG. 11A, 1111 represents holes for bolts; 1112 representsa cathode in the FCC; 1113 represents an electrolyte in the FCC; 1114represents an anode in the FCC; 1115 represents gas channels in theelectrodes (anode and cathode); 1116 represents an integratedmulti-fluid heat exchanger in the FCC. In an embodiment, there is nobarrier layer between the cathode and the electrolyte.

Referring to FIG. 11C, 1130 represents holes for bolts in the FCC; 1131represents air inlet; 1132 represents air outlet; 1133 represents fuelinlet; 1134 represents fuel outlet; 1135 represents bottom of the FCC;1136 represents top of the FCC. FIG. 11C illustrates the top view andbottom view of an embodiment of a FCC, in which the length of theoxidant side of the FCC is shown L_(o), the length of the fuel side ofthe FCC is shown L_(f), the width of the oxidant (air) entrance is shownW_(o), the width of the fuel entrance is shown W_(f). In FIG. 11C, twofluid exits are shown (Air Outlet 1132 and Fuel Outlet 1134). In somecases, the anode exhaust and the cathode exhaust are mixed and extractedthrough one fluid exit.

Referring to FIG. 11B, 1121 represents electrical bolt isolation; 1125represents anode; 1123 represents seal that seals the anode from airflow; 1126 represents cathode; 1124 represents seal that seals thecathode from fuel flow. FIG. 11B illustrates cross-sectional views ofthe FCC, wherein air flow is sealed from the anode and fuel flow issealed from the cathode. The bolts are isolated electrically with a sealas well. In various embodiments, the seal is a dual functional seal(DFS) comprising YSZ (yttria-stabilized zirconia) or a mixture of 3YSZ(3 mol % Y₂O₃ in ZrO₂) and 8YSZ (8 mol % Y₂O₃ in ZrO₂). In embodiments,the DFS is impermeable to non-ionic substances and electricallyinsulating. In an embodiment, the mass ratio of 3YSZ/8YSZ is in therange of from 10/90 to 90/10. In an embodiment, the mass ratio of3YSZ/8YSZ is about 50/50. In an embodiment, the mass ratio of 3YSZ/8YSZis 100/0 or 0/100.

Herein disclosed is a fuel cell cartridge (FCC) comprising an anode, acathode, an electrolyte, an interconnect, a fuel entrance on a fuel sideof the FCC, an oxidant entrance on an oxidant side of the FCC, at leastone fluid exit, wherein the fuel entrance has a width of W_(f), the fuelside of the FCC has a length of L_(f), the oxidant entrance has a widthof W_(o), the oxidant side of the FCC has a length of L_(o), whereinW_(f)/L_(f) is in the range of 0.1 to 1.0, or 0.1 to 0.9, or 0.2 to 0.9,or 0.5 to 0.9, or 0.5 to 1.0 and W_(o)/L_(o) is in the range of 0.1 to1.0, or 0.1 to 0.9, or 0.2 to 0.9, or 0.5 to 0.9, or 0.5 to 1.0.

In an embodiment, said entrances and exit are on one surface of the FCCand said FCC comprises no protruding fluid passage on said surface. Inan embodiment, said surface is smooth with a maximum elevation change ofno greater than 1 mm, or no greater than 100 microns, or no greater than10 microns.

In an embodiment, the FCC comprises a barrier layer between theelectrolyte and the cathode or between the electrolyte and the anode orboth. In an embodiment, the FCC comprises dual functional seal that isimpermeable to non-ionic substances and electrically insulating. In anembodiment, said dual functional seal comprises YSZ (yttria-stabilizedzirconia) or a mixture of 3YSZ (3 mol % Y₂O₃ in ZrO₂) and 8YSZ (8 mol %Y₂O₃ in ZrO₂).

In an embodiment, said interconnect comprises no fluid dispersingelement and said anode and cathode comprise fluid dispersing components.In an embodiment, said interconnect comprises no fluid dispersingelement and said anode and cathode comprise fluid channels.

In an embodiment, the FCC is detachably fixed to a mating surface andnot soldered nor welded to said mating surface. In an embodiment, theFCC is bolted to or pressed to said mating surface. In an embodiment,said mating surface comprises matching fuel entrance, matching oxidantentrance, and at least one matching fluid exit.

Also discussed herein is a fuel cell cartridge (FCC) comprising ananode, a cathode, an electrolyte, an interconnect, a fuel entrance, anoxidant entrance, at least one fluid exit, wherein said entrances andexit are on one surface of the FCC and said FCC comprises no protrudingfluid passage on said surface. In an embodiment, said surface is smoothwith a maximum elevation change of no greater than 1 mm, or no greaterthan 100 microns, or no greater than 10 microns.

In an embodiment, the FCC comprises dual functional seal that isimpermeable to non-ionic substances and electrically insulating. In anembodiment, said interconnect comprises no fluid dispersing element andsaid anode and cathode comprise fluid dispersing components. In anembodiment, said interconnect comprises no fluid dispersing element andsaid anode and cathode comprise fluid channels.

In an embodiment, the FCC is detachably fixed to a mating surface andnot soldered nor welded to said mating surface. In an embodiment, theFCC is bolted to or pressed to said mating surface. In an embodiment,said mating surface comprises matching fuel entrance, matching oxidantentrance, and at least one matching fluid exit.

Further disclosed herein is an assembly comprising a fuel cell cartridge(FCC) and a mating surface, wherein the FCC comprises an anode, acathode, an electrolyte, an interconnect, a fuel entrance on a fuel sideof the FCC, an oxidant entrance on an oxidant side of the FCC, at leastone fluid exit, wherein the fuel entrance has a width of W_(f), the fuelside of the FCC has a length of L_(f), the oxidant entrance has a widthof W_(o), the oxidant side of the FCC has a length of L_(o), whereinW_(f)/L_(f) is in the range of 0.1 to 1.0, or 0.1 to 0.9, or 0.2 to 0.9,or 0.5 to 0.9, or 0.5 to 1.0 and W_(o)/L_(o) is in the range of 0.1 to1.0, or 0.1 to 0.9, or 0.2 to 0.9, or 0.5 to 0.9, or 0.5 to 1.0, whereinthe FCC is detachably fixed to the mating surface.

Preferably, the FCC is not soldered nor welded to said mating surface.In an embodiment, the FCC is bolted to or pressed to said matingsurface. In an embodiment, said mating surface comprises matching fuelentrance, matching oxidant entrance, and at least one matching fluidexit.

In an embodiment, said entrances and exit are on one surface of the FCCand said FCC comprises no protruding fluid passage on said surface. Inan embodiment, said surface is smooth with a maximum elevation change ofno greater than 1 mm, or no greater than 100 microns, or no greater than10 microns.

In an embodiment, said interconnect comprises no fluid dispersingelement and said anode and cathode comprise fluid dispersing components,such as fluid channels.

Discussed herein is a method comprising pressing or bolting together afuel cell cartridge (FCC) and a mating surface, said method excludingwelding or soldering together the FCC and the mating surface, whereinthe FCC comprises an anode, a cathode, an electrolyte, an interconnect,a fuel entrance on a fuel side of the FCC, an oxidant entrance on anoxidant side of the FCC, at least one fluid exit, wherein the fuelentrance has a width of W_(f), the fuel side of the FCC has a length ofL_(f), the oxidant entrance has a width of W_(o), the oxidant side ofthe FCC has a length of L_(o), wherein W_(f)/L_(f) is in the range of0.1 to 1.0, or 0.1 to 0.9, or 0.2 to 0.9, or 0.5 to 0.9, or 0.5 to 1.0and W_(o)/L_(o) is in the range of 0.1 to 1.0, or 0.1 to 0.9, or 0.2 to0.9, or 0.5 to 0.9, or 0.5 to 1.0, wherein the FCC and the matingsurface are detachable.

In an embodiment, said entrances and exit are on one surface of the FCCand said FCC comprises no protruding fluid passage on said surface. Inan embodiment, said surface is smooth with a maximum elevation change ofno greater than 1 mm, or no greater than 100 microns, or no greater than10 microns. In an embodiment, said interconnect comprises no fluiddispersing element and said anode and cathode comprise fluid dispersingcomponents. In an embodiment, said interconnect comprises no fluiddispersing element and said anode and cathode comprise fluid channels.

Herein disclosed is a fuel cell cartridge (FCC) comprising a fuel celland a fuel cell casing, wherein the fuel cell comprises an anode, acathode, and an electrolyte, wherein at least a portion of the fuel cellcasing is made of the same material as the electrolyte. In anembodiment, the electrolyte is in contact with the portion of the fuelcell casing made of the same material. In an embodiment, the electrolyteand the portion of the fuel cell casing are made of a dual functionalseal (DFS), wherein the DFS comprises 3YSZ (3 mol % Y₂O₃ in ZrO2) and8YSZ (8 mol % Y₂O₃ in ZrO2), wherein the mass ratio of 3YSZ/8YSZ is inthe range of from 100/0 to 0/100 or from 10/90 to 90/10 and wherein theDFS is impermeable to non-ionic substances and electrically insulating.In an embodiment, the mass ratio of 3YSZ/8YSZ is about 50/50 or 40/60 or60/40 or 30/70 or 70/30 or 20/80 or 80/20.

In an embodiment, said fuel cell casing comprises a fuel entrance andfuel passage for the anode, an oxidant entrance and oxidant passage forthe cathode, and at least one fluid exit. In an embodiment, saidentrances and exit are on one surface of the FCC and said FCC comprisesno protruding fluid passage on said surface. In an embodiment, the fuelcell casing is in contact with at least a portion of the anode.

In an embodiment, the FCC comprises a barrier layer between theelectrolyte and the cathode and between the fuel cell casing and thecathode. In an embodiment, the FCC comprises an interconnect, whereinthe interconnect comprises no fluid dispersing element and said anodeand cathode comprise fluid dispersing components. In an embodiment, theFCC comprises an interconnect, wherein the interconnect comprises nofluid dispersing element and said anode and cathode comprise fluidchannels.

In an embodiment, the FCC is detachably fixed to a mating surface andnot soldered nor welded to said mating surface. In an embodiment, saidmating surface comprises matching fuel entrance, matching oxidantentrance, and at least one matching fluid exit.

Also discussed herein is a dual functional seal (DFS) comprising 3YSZ (3mol % Y₂O₃ in ZrO2) and 8YSZ (8 mol % Y₂O₃ in ZrO2), wherein the massratio of 3YSZ/8YSZ is in the range of from 10/90 to 90/10 and whereinthe DFS is impermeable to non-ionic substances and electricallyinsulating. In an embodiment, the mass ratio of 3YSZ/8YSZ is about 50/50or 40/60 or 60/40 or 30/70 or 70/30 or 20/80 or 80/20. In an embodiment,the DFS is used as an electrolyte in a fuel cell or as a portion of afuel cell casing or both.

Further disclosed herein is a method comprising providing a dualfunctional seal (DFS) in a fuel cell system, wherein the DFS comprises3YSZ (3 mol % Y2O3 in ZrO₂) and 8YSZ (8 mol % Y₂O₃ in ZrO₂), wherein themass ratio of 3YSZ/8YSZ is in the range of from 100/0 to 0/100 or from10/90 to 90/10 and wherein the DFS is impermeable to non-ionicsubstances and electrically insulating. In an embodiment, the mass ratioof 3YSZ/8YSZ is about 50/50 or 40/60 or 60/40 or 30/70 or 70/30 or 20/80or 80/20.

In an embodiment, the DFS is used as electrolyte or a portion of a fuelcell casing or both in the fuel cell system. In an embodiment, saidportion of a fuel cell casing is the entire fuel cell casing. In anembodiment, said portion of a fuel cell casing is a coating on the fuelcell casing. In an embodiment, the electrolyte and said portion of afuel cell casing are in contact.

Disclosed herein is a fuel cell system comprising an anode having sixsurfaces, a cathode having six surfaces, an electrolyte, and an anodesurround in contact with at least three surfaces of the anode, whereinthe electrolyte is part of the anode surround and said anode surround ismade of the same material as the electrolyte. In an embodiment, saidsame material is a dual functional seal (DFS) comprising 3YSZ (3 mol %Y2O3 in ZrO2) and 8YSZ (8 mol % Y2O3 in ZrO2), wherein the mass ratio of3YSZ/8YSZ is in the range of from 100/0 to 0/100 or from 10/90 to 90/10and wherein the DFS is impermeable to non-ionic substances andelectrically insulating. In an embodiment, the mass ratio of 3YSZ/8YSZis about 50/50 or 40/60 or 60/40 or 30/70 or 70/30 or 20/80 or 80/20.

In an embodiment, the anode surround is in contact with five surfaces ofthe anode. In an embodiment, the fuel cell system comprises a barrierlayer between the cathode and a cathode surround, wherein the barrierlayer is in contact with at least three surfaces of the cathode, whereinthe electrolyte is part of the cathode surround and said cathodesurround is made of the same material as the electrolyte.

In an embodiment, the fuel cell system comprises fuel passage andoxidant passage in the anode surround and the cathode surround. In anembodiment, the fuel cell system comprises an interconnect, wherein theinterconnect comprises no fluid dispersing element and said anode andcathode comprise fluid dispersing components. In an embodiment, the fuelcell system comprises an interconnect, wherein the interconnectcomprises no fluid dispersing element and said anode and cathodecomprise fluid channels.

Matching SRTs

In this disclosure, SRT refers to a component of the strain rate tensor.Matching SRTs is contemplated in both heating and cooling processes. Ina fuel cell, multiple materials or compositions exist. These differentmaterials or compositions often have different thermal expansioncoefficients. As such, the heating or cooling process often causesstrain or even cracks in the material. We have unexpectedly discovered atreating process (heating or cooling) to match the SRTs of differentmaterials/compositions to reduce, minimize, or even eliminateundesirable effects.

Herein discussed is a method of making a fuel cell, wherein the fuelcell comprises a first composition and a second composition, the methodcomprising heating the first and second compositions, wherein the firstcomposition has a first SRT and the second composition has a second SRT,such that the difference between the first SRT and the second SRT is nogreater than 75% of the first SRT. As an illustration, FIG. 7 shows theSRTs of a first composition and a second composition as a function oftemperature.

In an embodiment, wherein the SRTs are measured in mm/min. In anembodiment, the difference between the first SRT and the second SRT isno greater than 50% or 30% or 20% of the first SRT. In an embodiment,heating is achieved via at least one of the following: conduction,convection, radiation. In an embodiment, heating compriseselectromagnetic radiation (EMR). In an embodiment, EMR comprises UVlight, near ultraviolet light, near infrared light, infrared light,visible light, laser, electron beam.

In an embodiment, the first composition and the second composition areheated at the same time. In an embodiment, the first composition and thesecond composition are heated at different times. In an embodiment, thefirst composition is heated for a first period of time, the secondcomposition is heated for a second period of time, wherein at least aportion of the first period of time overlaps with the second period oftime.

In an embodiment, heating takes places more than once for the firstcomposition, or for the second composition, or for both. In anembodiment, the first composition and the second composition are heatedat different temperatures. In an embodiment, the first composition andthe second composition are heated using different means. In anembodiment, the first composition and the second composition are heatedfor different periods of time. In an embodiment, heating the firstcomposition causes at least partial heating of the second composition,for example, via conduction. In an embodiment, heating causesdensification of the first composition, or the second composition, orboth.

In an embodiment, the first composition is heated to achieve partialdensification resulting in a modified first SRT; and then the first andsecond compositions are heated such that the difference between themodified first SRT and the second SRT is no greater than 75% of thefirst modified SRT. In an embodiment, the first composition is heated toachieve partial densification resulting in a modified first SRT, thesecond composition is heated to achieve partial densification resultingin a modified second SRT; and then the first and second compositions areheated such that the difference between the modified first SRT and thesecond modified SRT is no greater than 75% of the first modified SRT.

In an embodiment, the fuel cell comprises a third composition having athird SRT. In an embodiment, the third composition is heated such thatthe difference between the first SRT and the third SRT is no greaterthan 75% of the first SRT. In an embodiment, the third composition isheated to achieve partial densification resulting in a modified thirdSRT; and then the first and second and third compositions are heatedsuch that the difference between the first SRT and the modified thirdSRT is no greater than 75% of the first SRT. In an embodiment, the firstand second and third compositions are heated to achieve partialdensification resulting in a modified first SRT, a modified second SRT,and a modified third SRT; and then the first and second and thirdcompositions are heated such that the difference between the modifiedfirst SRT and the modified second SRT is no greater than 75% of themodified first SRT and the difference between the modified first SRT andthe modified third SRT is no greater than 75% of the modified first SRT.

In various embodiments, the method produces a crack free electrolyte inthe fuel cell. In various embodiments, heating is performed in situ. Invarious embodiments, heating causes sintering or co-sintering or both.In various embodiments, heating takes place for no greater than 30minutes, or no greater than 30 seconds, or no greater than 30milliseconds.

Referring to FIG. 8, in an embodiment, a process flow diagram is shownfor forming and heating at least a portion of a fuel cell. 810represents forming composition 1. 820 represents heating composition 1at temperature T1 for time t1. 830 represents forming composition 2. 840represents heating composition 1 and composition 2 simultaneously attemperature T2 for time t2, wherein at T2, the difference between SRT ofcomposition 1 and SRT of composition 2 is no greater than 75% of SRT ofcomposition 1. Alternatively, 840 represents heating composition 1 andcomposition 2 simultaneously at temperature T2 and T2′ (for example,using different heating mechanisms) for time t2, wherein at T2 and T2′,the difference between SRT of composition 1 and SRT of composition 2 isno greater than 75% of SRT of composition 1.

EXAMPLES

The following examples are provided as part of the disclosure of variousembodiments of the present invention. As such, none of the informationprovided below is to be taken as limiting the scope of the invention.

Example 1. Making a Fuel Cell Stack

Example 1 is illustrative of the preferred method of making a fuel cellstack. The method uses an AMM model no. 0012323 from Ceradrop and an EMRmodel no. 092309423 from Xenon Corp. An interconnect substrate is putdown to start the print.

As a first step, an anode layer is made by the AMM. This layer isdeposited by the AMM as a slurry A, having the composition as shown inthe table below. This layer is allowed to dry by applying heat via aninfrared lamp. This anode layer is sintered by hitting it with anelectromagnetic pulse from a xenon flash tube for 1 second.

An electrolyte layer is formed on top of the anode layer by the AMMdepositing a slurry B, having the composition shown in the table below.This layer is allowed to dry by applying heat via an infrared lamp. Thiselectrolyte layer is sintered by hitting it with an electromagneticpulse from a xenon flash tube for 60 seconds.

Next a cathode layer is formed on top of the electrolyte layer by theAMM depositing a slurry C, having the composition shown in the tablebelow. This layer is allowed to dry by applying heat via an infraredlamp. This cathode layer is sintered by hitting it with anelectromagnetic pulse from a xenon flash tube for ½ second.

An interconnect layer is formed on top of the cathode layer by the AMMdepositing a slurry D, having the composition shown in the table below.This layer is allowed to dry by applying heat via an infrared lamp. Thisinterconnect layer is sintered by hitting it with an electromagneticpulse from a xenon flash tube for 30 seconds.

These steps are then repeated 60 times, with the anode layers beingformed on top of the interconnects. The result is a fuel cell stack with61 fuel cells.

Composition of Slurries Slurry Solvents Particles A 100% isopropylalcohol 10 wt % NiO-8YSZ B 100% isopropyl alcohol 10 wt % 8YSZ C 100%isopropyl alcohol 10 wt % LSCF D 100% isopropyl alcohol 10 wt %lanthanum chromite

Example 2. LSCF in Ethanol

Mix 200 ml of ethanol with 30 grams of LSCF powder in a beaker.Centrifuge the mixture and obtain an upper dispersion and a lowerdispersion. Extract and deposit the upper dispersion using a 3D printeron a substrate and form a LSCF layer. Use a xenon lamp (10 kW) toirradiate the LSCF layer at a voltage of 400V and a burst frequency of10 Hz for a total exposure duration of 1,000 ms.

Example 3. CGO in Ethanol

Mix 200 ml of ethanol with 30 grams of CGO powder in a beaker.Centrifuge the mixture and obtain an upper dispersion and a lowerdispersion. Extract and deposit the upper dispersion using a 3D printeron a substrate and form a CGO layer. Use a xenon lamp (10 kW) toirradiate the CGO layer at a voltage of 400V and a burst frequency of 10Hz for a total exposure duration of 8,000 ms.

Example 4. CGO in Water

Mix 200 ml of deionized water with 30 grams of CGO powder in a beaker.Centrifuge the mixture and obtain an upper dispersion and a lowerdispersion. Extract and deposit the upper dispersion using a 3D printeron a substrate and form a CGO layer. Use a xenon lamp (10 kW) toirradiate the CGO layer at a voltage of 400V and a burst frequency of 10Hz for a total exposure duration of 8,000 ms.

Example 5. NiO in Water

Mix 200 ml of deionized water with 30 grams of NiO powder in a beaker.Centrifuge the mixture and obtain an upper dispersion and a lowerdispersion. Extract and deposit the upper dispersion using a 3D printeron a substrate and form a NiO layer. Use a xenon lamp (10 kW) toirradiate the NiO layer at a voltage of 400V and a burst frequency of 10Hz for a total exposure duration of 15,000 ms.

Example 6. Sintering Results

Referring to FIG. 10, an electrolyte 1001 (YSZ) is printed and sinteredon an electrode 1002 (NiO—YSZ). The scanning electron microscopy imageshows the side view of the sintered structures, which demonstratesgas-tight contact between the electrolyte and the electrode, fulldensification of the electrolyte, and sintered and porous electrodemicrostructures.

Example 7. Fuel Cell Stack Configurations

A 48-Volt fuel cell stack has 69 cells with about 1000 W of poweroutput. The fuel cell in this stack has a dimension of about 4 cm×4 cmin length and width and about 0.7 cm in height. A 48-Volt fuel cellstack has 69 cells with about 5000 W of power output. The fuel cell inthis stack has dimensions of about 8.5 cm×8.5 cm in length and width andabout 0.7 cm in height.

It is to be understood that this disclosure describes exemplaryembodiments for implementing different features, structures, orfunctions of the invention. Exemplary embodiments of components,arrangements, and configurations are described to simplify the presentdisclosure; however, these exemplary embodiments are provided merely asexamples and are not intended to limit the scope of the invention. Theembodiments as presented herein may be combined unless otherwisespecified. Such combinations do not depart from the scope of thedisclosure.

Additionally, certain terms are used throughout the description andclaims to refer to particular components or steps. As one skilled in theart appreciates, various entities may refer to the same component orprocess step by different names, and as such, the naming convention forthe elements described herein is not intended to limit the scope of theinvention. Further, the terms and naming convention used herein are notintended to distinguish between components, features, and/or steps thatdiffer in name but not in function.

While the disclosure is susceptible to various modifications andalternative forms, specific embodiments thereof are shown by way ofexample in the drawings and description. It should be understood,however, that the drawings and detailed description are not intended tolimit the disclosure to the particular form disclosed, but on thecontrary, the intention is to cover all modifications, equivalents andalternatives falling within the spirit and scope of this disclosure.

What is claimed is:
 1. A method of making a fuel cell comprising:forming an anode using an additive manufacturing machine; forming acathode using the additive manufacturing machine; and forming anelectrolyte using the additive manufacturing machine, wherein theelectrolyte is between the anode and the cathode.
 2. The method of claim1, wherein electrical current flow is perpendicular to the electrolytein the lateral direction when the fuel cell is in use.
 3. The method ofclaim 1 comprising making at least one barrier layer using the additivemanufacturing machine or making a catalyst layer using the additivemanufacturing machine.
 4. The method of claim 1 comprising making aninterconnect using the additive manufacturing machine.
 5. The method ofclaim 1 comprising heating the anode, or the electrolyte, or thecathode, or combinations thereof.
 6. The method of claim 6, whereinheating is performed using electromagnetic radiation (EMR).
 7. Themethod of claim 7, wherein the electromagnetic radiation has awavelength ranging from 10 to 1500 nm and the EMR has a minimum energydensity of 0.1 Joule/cm².
 8. The method of claim 7, wherein theelectromagnetic radiation is applied using a xenon lamp.
 9. The methodof claim 6, wherein heating is performed in situ.
 10. The method ofclaim 1, wherein said additive manufacturing machine utilizes amulti-nozzle additive manufacturing method.
 11. The method of claim 1,wherein said additive manufacturing machine utilizes a deposition methodcomprising material jetting, binder jetting, inkjet printing, aerosoljetting, or aerosol jet printing, vat photopolymerization, powder bedfusion, material extrusion, directed energy deposition, sheetlamination, ultrasonic inkjet printing, or combinations thereof.
 12. Anadditive manufacturing machine comprising a chamber, wherein saidchamber is configured to receive a material and configured to allow thematerial to be heated and reach a temperature of at least 300° C. 13.The additive manufacturing machine of claim 13, wherein said materialforms a portion of a fuel cell.
 14. The additive manufacturing machineof claim 13, wherein said chamber is configured to heat the material insitu.
 15. The additive manufacturing machine of claim 13, wherein saidchamber is heated by electromagnetic radiation (EMR), plasma, hot fluid,a heating element, or combinations thereof.
 16. The additivemanufacturing machine of claim 13, wherein said chamber is configured tobe filled with a fluid.
 17. The additive manufacturing machine of claim17, wherein said fluid comprises an inert gas with no significant amountof oxygen.
 18. The additive manufacturing machine of claim 13 configuredto deploy material jetting, binder jetting, inkjet printing, aerosoljetting, or aerosol jet printing, vat photopolymerization, powder bedfusion, material extrusion, directed energy deposition, sheetlamination, ultrasonic inkjet printing, or combinations thereof.
 19. Asystem comprising at least one deposition nozzle, an electromagneticradiation (EMR) source, and a deposition receiver, wherein thedeposition receiver is configured to receive both electromagneticradiation exposure and deposition.
 20. The system of claim 20, whereinthe deposition receiver is configured to receive both electromagneticradiation exposure and deposition at the same location.
 21. The systemof claim 20, wherein the deposition receiver is configured to move suchthat the receiver receives deposition for a first time period and toreceive electromagnetic radiation exposure for second time period.